<PAGE>

                                                                   Exhibit 10.15

                                   GROSS LEASE

                                    Landlord

                     PRINCIPAL MUTUAL LIFE INSURANCE COMPANY

                                       and

                                     Tenant

                              OPEN SOLUTIONS, INC.

                                     Dated:

                                February 29, 1996

                                    Premises:

                             300 WINDING BROOK DRIVE
                            GLASTONBURY, CONNECTICUT
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                                Table of Contents

      Article                                                             Page
      -------                                                             ----

1.    PREMISES .........................................................    1

2.    DEFINITIONS ......................................................    1

3.    TERM .............................................................    2

4.    USE OF PREMISES ..................................................    2

5     RENT .............................................................    3

6.    CONSTRUCTION .....................................................    3

7.    ADDITIONAL RENT ..................................................    4

8.    INCREASE IN REAL ESTATE TAXES ....................................    5

9.    ALTERATIONS, IMPROVEMENTS, ETC ...................................    6

10.   REPAIRS ..........................................................    6

11.   PARKING ..........................................................    6

12.   UTILITIES AND SERVICES ...........................................    6

      (a)   HVAC .......................................................    6
      (b)   Water ......................................................    6
      (c)   Electricity ................................................    6
      (d)   Cleaning ...................................................    7
      (e)   Security ...................................................    7
      (f)   Interruption of Services ...................................    7
13.   INSURANCE ........................................................    8

14.   SUBORDINATION ....................................................    8

15.   DESTRUCTION, FIRE OR OTHER CAUSES ................................    9

16.   EMINENT DOMAIN ...................................................   10

17.   SUBLETTING .......................................................   10

18.   FEES AND EXPENSES ................................................   11

19.   NO REPRESENTATIONS BY LANDLORD, ETC ..............................   11

20.   QUIET ENJOYMENT ..................................................   12

21.   DEFAULT ..........................................................   12

22.   REMEDIES OF LANDLORD .............................................   13

23.   RIGHT TO EXHIBIT PREMISES AND ACCESS TO PREMISES .................   14


                                        i
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      Article                                                             Page
      -------                                                             ----

24.   RULES AND REGULATIONS ............................................   14

25.   BROKERAGE ........................................................   14

26.   FORCE MAJEURE ....................................................   14

27.   SECURITY DEPOSIT .................................................   15

28.   LEASE STATUS AND NOTICE ..........................................   15

29.   ASSIGNS ..........................................................   16

30.   OPTION TO EXTEND .................................................   16

31.   EXPANSION OPTION .................................................   17

32.   SIGNAGE ..........................................................   18

33.   SEVERABILITY .....................................................   18

34.   SURRENDER OF PREMISES ............................................   18

35.   GOVERNING LAW ....................................................   18

36.   LITIGATION EXPENSES ..............................................   18

Exhibits

      A -- Description of Demised Premises (Floor Plan)

      B -- Property Description

      C -- Work Letter/Tenant Improvement Allowance

      D -- Building Rules and Regulations


                                       ii
<PAGE>

      Lease dated the 29 day of February, 1996, by and between Principal Mutual
Life Insurance Company, an Iowa Corporation, with an office at 711 High Street,
Des Moines, Iowa, 50392 ("Landlord") and Open Solutions, Inc., with an office at
300 Winding Brook Drive, Glastonbury, Connecticut ("Tenant").

                                   WITNESSETH:

      1. PREMISES. Landlord hereby leases to Tenant, for the terms and upon the
rentals hereinafter specified, the following premises: approximately 14,275
rentable square feet (the "Premises") on the 1st floor in the building known as
300 Winding Brook Drive, Glastonbury, Connecticut (the "City"). The Premises are
described on Exhibit A attached hereto and made a part hereof. Said building and
the land shown on Exhibit B hereto are herein collectively referred to as the
"Building".

      2. DEFINITIONS. Terms used in this Lease shall have the following
meanings:

            (i)   Base Rent: $1,191,010.83

            Lease Years  Annual Base Rent  Monthly Installment
            -----------  ----------------  -------------------

                  1         $ 83,270.83      $11,895.83
                  2         $149,173.75      $12,431.15
                  3         $163,448.75      $13,620.73
                  4         $177,723.75      $14,810.31
                  5         $185,575.00      $15,464.58
                  6         $214,125.00      $17,843.75
                  7         $217,693.75      $18,141.15

            (ii)  Tax Base Year: Calendar Year 1996
                  Base Year:     Calendar Year 1996

            (iii) Tenant's Proportionate Share: 46.2%

            (iv)  Number of parking spaces available for Tenant's use: 56, based
                  upon four spaces per 1,000 rentable square feet leased.

            (v)   The Brokers: William Raveis Real Estate
                               Servus Management Corporation

            (vi)  Lease Year: Consecutive 12 month periods during the Term, with
                  the first Lease Year commencing on the first day of the month
                  in which the Commencement Date falls.
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                                        2


      3. TERM. TO HAVE AND TO HOLD the Premises for a term (the "Term"),
commencing on a date (the "Commencement Date") which shall be the earlier of (a)
May 1, 1996 or (b) the date premises will be made availabe for tenant's
occupancy, and ending on April 30, 2003. thereafter (the "Expiration Date"),
unless the Term shall sooner terminate pursuant to any of the terms, covenants
or conditions of this Lease or pursuant to law. Anything herein to the contrary
notwithstanding, the first monthly installment of Base Rent shall be payable on
the execution hereof. If the Tenant occupies the space earlier than May 1, 1996,
an addendum will be attached to this lease which will define the amended
Commencement Date and Expiration Date.

      4. USE OF PREMISES. (a) Tenant shall use the Premises only for general and
administrative offices and for no other purpose. Except as provided herein, no
signs of any kind shall be installed or maintained on the exterior of the
Building, or in the Premises which shall be visible form outside the Building,
without the prior written consent of Landlord and without conforming said sign
to local ordinances. Such consent shall not be unreasonably withheld. Tenant
will not interfere with the conduct of business by other tenants or occupants of
the Building or permit actions constituting a private nuisance, including
without limitation, the occupation by Tenant or its employees, agents or
invitees of more than the number of parking places allocated to Tenant. In
connection with, and incidental to, Tenant's use of the Premises as provided in
this subsection, Tenant, at its sole cost and expense and upon compliance with
all applicable legal requirements, may install a microwave or convection ovens,
kitchenettes and dishwashers in the Premises for the purpose of warming or
re-heating food for the employees and business guests of Tenant (but not for use
as a public restaurant), provided that Tenant shall obtain all permits required
by any governmental authorities for the operation thereof and such installation
shall comply with the provisions of this Lease.

            (b) Tenant, at its expense, shall comply with all laws, orders and
regulations of Federal, State and municipal authorities and with any direction
of any public officer or officers, pursuant to law, which shall impose any
violation, order or duty upon Landlord or Tenant with respect to the Premises or
the use or occupancy thereof; including without limitation the Americans With
Disabilities Act (as amended from time to time and as may be superseded from
time to time, the "Act") and any environmental laws, including without
limitation structural changes. Anything in the preceding sentence to the
contrary notwithstanding, if alterations to the Premises are required under the
Act because of the type of business of another tenant of the Building,
alterations made to its space by another tenant of the Building or alterations
to the common areas of the Building (the "Common Areas") made by Landlord, then
Landlord shall, at its expense, make the alterations to the Premises required
under the Act. To the best of Landlord's knowledge, the Common Areas comply with
applicable laws, codes and regulations, including the Act.

            (c) Tenant shall not do or permit to be done any act or thing upon
the Premises which will invalidate or be in conflict with fire, public liability
or other insurance policies covering the Building. Tenant, at its expense, shall
comply with all rules, orders, regulations and requirements of the Board of Fire
Underwriters or other similar body or authority having jurisdiction and shall
not do or permit anything to be done in or upon the Premises or the Building, or
bring or keep anything
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                                        3


therein, which is prohibited by the fire department or any of such Boards of
Fire Underwriters or other body or authority or which would increase the rate of
fire insurance applicable to the Building over that in effect on the
Commencement Date of this Lease. If, by reason of failure to comply with the
provisions of the Section 4, any insurance rate for the Building shall, on the
Commencement Date or at any time thereafter, be higher than it otherwise would
be, then Tenant upon demand shall reimburse Landlord, as Additional Rent
hereunder, for that part of all insurance premiums thereafter paid by Landlord
which shall have been charged because of such failure by Tenant.

            (d) Tenant shall, at Tenant's expense, keep and maintain the
Premises in compliance with all local, state and Federal environmental laws,
ordinances and regulations, including without limitation ss.ss. 22a-448 through
22a-457 of the Connecticut General Statutes, 42 U.S.C. ss.9601 et seq., 42
U.S.C. ss.6901 et seq., 49 U.S.C. ss.1801 et seq., and the regulations
promulgated thereunder, (all of the foregoing being referred to collectively as
the "Environmental Laws"). During the Lease term, Tenant shall permit no spills,
discharges, or releases of any hazardous, radioactive or polluting substances,
including without limitation any oil or petroleum products or any chemical
liquids or solids (all of the foregoing being referred to collectively as
"Hazardous Materials"). In addition to the matters provided for in subsection 13
(c), Tenant will indemnify, defend and hold harmless Landlord, its successors
and assigns from and against any claim, liability, cost, damage, expense,
response or remedial action costs (including without limitation attorneys' fees,
and costs of investigation or audit) relating to: (i) the presence, use or
storage on or under the Premises, or any spill, discharge or release from the
Premises, of any Hazardous Material during the Lease term; (ii) any failure of
the Premises to comply with any applicable Environmental Law, unless such
noncompliance results from the conduct of Landlord and/or a prior occupant; or
(iii) any loss of value of the Premises, including without limitation any loss
of value arising from the imposition of any lien against the Premises, unless
such loss of value of the Premises, including without limitation any loss of
value arising from the imposition of any lien against the Premises, unless such
loss of value results from the conduct of Landlord and/or a prior occupant. The
foregoing indemnity shall survive the expiration or termination of this Lease,
and any claim hereunder must be made within five years after such expiration or
termination.

      5. RENT. Commencing on the Commencement Date, Tenant receives a rent
concession in months 1, 2, 3, 6 and 7 in year 1 by Landlord. Tenant shall begin
paying rent to Landlord in months 4 and 5, and then resume regular monthly
payments in month 8. Tenant shall pay to Landlord the Base Rent without demand
and without setoff or deductions of any kind, in equal monthly installments, in
advance, on the first day of each calendar month of the Term at the address of
Landlord stated above or such other place as Landlord may designate in writing
form time to time, with payment in advance of appropriate fractions of a monthly
payment for any portion of a month at the expiration or prior termination of the
Term. Every amount payable by Tenant hereunder in addition to Base Rent and
Additional Rent are herein collectively referred to as the "Rent". Any Rent not
paid by Tenant on or before the due date thereof shall thereafter be payable
with a late charge equal to 5% of the unpaid installment, payable as Additional
Rent.

      6. CONSTRUCTION.

            See Exhibit C attached hereto.
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                                        4


      7. ADDITIONAL RENT. (a) After the expiration of the Base Year and of each
succeeding calendar year ("Operating Year"), Landlord shall furnish Tenant a
written statement prepared by Landlord of the Operating Expenses of the
Building, as defined in paragraph 7.(b) herein, incurred for such year. During
the period of 60 days after receipt of Landlord's statement, Tenant may inspect
and audit the records of the material reflected in said Landlord's statement at
a reasonable time mutually agreeable to Landlord and Tenant. Failure of Tenant
to challenge any item in such statement within 90 days after receipt shall be a
waiver of Tenant's right to challenge such item for such year. Within 30 days
after receipt of such statement for any Operating Year setting forth any
increase of Operating Expenses during such Operating Year over the Operating
Expenses in the Base Year (said increase being referred to herein as the "Cost
Increase", Tenant shall pay Tenant's Proportionate Share of the Cost Increase
(less the amount of Tenant's projected share paid by Tenant on account thereof)
to Landlord as Additional Rent.

            (b) The Operating Costs of the Building are hereby defined to
include all charges for management fees, all charges for security, heat, air
conditioning, utilities, insurance, janitorial and cleaning services; all
salaries, wages, payroll taxes, and other personnel costs of engineers,
superintendents, watchmen and other building workers or employees; all charges
under maintenance, and service contracts or for on-call services for chillers,
boilers, controls and/or elevators; all charges for landscaping, window
cleaning, and building grounds, plaza and parking lot maintenance; all charges
for personal property taxes (if any) in connection with personal property used
in the operation of the Building; all costs of licenses and permits of Building
operation and maintenance; and all other maintenance operation, services or
repair, excluding major component replacement, expenses and costs of supplies
expended in connection with the Building, the suites therein, or the real
property, which charges are or may be deducted (and not capitalized) for Federal
Income Tax purposes; and also including straight line depreciation intention of
lowering of Operating Costs.

            (c) Commencing with the first Operating Year, Tenant shall pay to
Landlord, as Additional Rent, Tenant's projected share. Such projected share
shall be equal to Landlord's Increase for the Operating Year. On the first day
of each month of each Operating Year during the Term, and within 30 days after
Tenant's receipt of Landlord's written estimate, Tenant shall pay to Landlord
one-twelfth of its projected share of the estimated Cost Increase for such
Operating Year. If Landlord's statement after the end of an Operating Year shall
indicate that Tenant's projected share exceeded Tenant's Proportionate Share of
Cost Increase, Landlord shall forthwith, at Landlord's option, either (i) pay
the amount of excess directly to Tenant concurrently with the notice or (ii)
permit Tenant to credit the amount of such excess against the subsequent
payments of Additional Rent due hereunder. If Landlord's statement shall
indicate that Tenant's Proportionate Share of Cost Increase exceeded Tenant's
projected share for the completed Operating Year, Tenant shall, subject to the
provisions of subsection 7 (a) herein, pay the amount of such excess to Landlord
within 30 days after demand. If said Landlord's statement is furnished to Tenant
after the commencement of a subsequent Operating Year, there shall be promptly
paid by Tenant to Landlord or vice versa, as the case may be, an amount equal to
the portion of such payment or credit allocable to the part of such Operating
Year which shall have elapsed prior to the first day of the calendar month next
succeeding the calendar month in which said Landlord's statement is furnished to
Tenant.
<PAGE>

                                        5


            (d) Landlord's failure to render Landlord's statement with respect
to any Operating Year or Tax Year, or Landlord's delay in rendering said
statement beyond a date specified herein, shall not prejudice Landlord's right
to render a Landlord's statement with respect to that or any subsequent
Operating Year or Tax Year; provided, however, that Landlord's failure to render
a statement within two years after the end of any Operating Year or Tax Year
shall be deemed a waiver of Landlord's right to render a Landlord's statement
for such year. The obligations of Landlord and Tenant under the provisions of
this Section with respect to any Additional Rent, which obligations have accrued
prior to the expiration or sooner termination of the Term, shall survive the
expiration or any sooner termination of the Term. Any dispute under this Section
shall be determined by arbitration in Hartford, Connecticut, under the then
commercial rules of the American Arbitration Association, and any award shall be
binding upon the parties.

      8. INCREASE IN REAL ESTATE TAXES. (a) If Real Estate Taxes with respect to
the Building are increased, during any year subsequent to the Tax Base Year,
over Real Estate Taxes paid by Landlord during the Tax Base Year, then Tenant
shall pay to Landlord, without setoff or deductions of any kind, except as
specified in this Lease, as Additional Rent, an amount equal to Tenant's
Proportionate Share of such increase. Payment of such increase shall be made in
the installments provided by the taxing authority within 30 days after Tenant
receives from Landlord notice of such tax increase and a bill for Tenant's
Proportionate Share thereof; together with a copy of the applicable bill
received by Landlord from the taxing authority. "Real Estate Taxes" shall mean
all taxes or assessments and governmental charges, whether Federal, State or
municipal, which are levied or charged against real estate, personal property
within the Building or rents, or on the right or privilege of leasing real
estate or collecting rents thereon and any other taxes and assessments
attributable to the Building or its operation, excluding, however, Federal,
State or other general income taxes not limited to real property. If the
Building shall not be assessed as if it were 95% occupied during the Tax Base
Year, then for the Tax Base Year and each subsequent year, Real Estate Taxes
shall be adjusted as if the Building were 95% occupied during each such year. If
Landlord shall be required under a mortgage or other creditor arrangement to
make real estate tax deposits monthly or otherwise, Tenant shall make the same
installment payments to Landlord of its share of same.

            (b) Notwithstanding anything to the contrary set forth in this
Lease, Real Estate Taxes shall not include (i) any excess profit taxes,
franchise taxes, gift taxes, capital stock taxes, inheritance and succession
taxes, estate taxes, general federal and state income taxes, and other taxes to
the extent applicable to Landlord's general or net income (as opposed to rents
or receipts); (ii) penalties incurred as a result of Landlord's negligence,
inability or unwillingness to make payments of, and/or to file any tax or
informational returns with respect to, any Real Estate Taxes, when due; (iii)
any other taxes or assessments charged or levied against Landlord which are not
directly incurred as a result of the ownership or operation of the Building; and
(iv) any real estate taxes directly payable by Tenant or any other tenant in the
Building under the applicable provisions in their respective leases.
<PAGE>

                                        6


      9. ALTERATIONS. IMPROVEMENTS. ETC. (a) Alterations, improvements or
additions made by Landlord or Tenant upon the Premises or in or on the Building
outside the Premises, except furniture, light fixtures, equipment, or movable
partitions or trade fixtures installed at the expense of Tenant, shall be the
property of Landlord and shall remain and be surrendered with the Premises as a
part thereof at the termination of this Lease, without compensation to Tenant,
unless Landlord shall require Tenant to remove same.

            (b) Tenant shall not make any alterations, installations or
improvements in the Premises without Landlord's prior written consent, which
consent shall not be unreasonably withheld.

      10. REPAIRS. (a) The exterior (excluding windows) and structure of the
Building and all parts of the heating, plumbing, electrical and air conditioning
systems, except those portions within the Premises (and any supplemental HVAC
units installed by or for Tenant), shall be maintained and repaired by Landlord,
except if necessitated by the excess use (i.e., greater than normal office use)
by, or the negligence or wrongful act of Tenant, its employees, agents or
invitees, in which event Tenant shall be responsible for repair or replacement
as necessary.

            (b) Tenant, at its expense, shall repair, maintain in good order and
condition and replace, if necessary, the interior of the Premises and the
Building systems therein. Tenant shall keep the Premises clean and orderly in
accordance with Landlord's standards for the Building.

      11. PARKING. Landlord shall maintain the Building's parking lot to be used
by Tenant in common with other tenants of the Building. Tenant shall have the
right to use the number of unreserved parking spaces specified in Section 2
hereof. Landlord shall have the right, at any time and from time to time during
the Term, to designate the parking spaces to be used by Tenant, in which event
Tenant shall limit its employee and invitee parking to its assigned spaces and
will post markings designating its spaces. Landlord shall have no liability to
Tenant if others park in Tenant's assigned spaces. Landlord shall maintain the
parking lot and sidewalks in good and orderly condition, including but not
limited to reasonably prompt snow removal.

      12. UTILITIES AND SERVICES. (a) HVAC. Mondays through Fridays from 8:00
a.m. to 6:00 p.m. and Saturdays from 8:00 a.m. to 12:00 p.m. (except the days
observed by the Federal or the Connecticut state governments as legal holidays),
Landlord shall furnish and distribute to the Premises air conditioning and heat
with a system designed to maintain an indoor condition of 78(degree) F dry bulb
when the outdoor condition is 100(degree) F dry bulb and an indoor condition of
68(degree) F dry bulb when the outdoor condition is 0(degree) F dry bulb.

            (b) Water. Landlord shall supply reasonably adequate quantities of
hot and cold water to the Premises for ordinary lavatory and drinking purposes
and for Tenant's kitchen area.

            (c) Electricity. (i) Landlord shall cause electric service to be
supplied for lighting the Premises and for the operation of ordinary office
equipment, with a capacity of seven watts per rentable square foot, and for
HVAC, the cost of which shall be included in Operating Expenses.
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                                        7


                  (ii) Landlord shall have the exclusive right, at Tenant's
expense, to make any replacement of lamps, fluorescent tubes and lamp ballasts
in the Premises. Landlord may adopt a system of relamping and ballast
replacement periodically on a group basis in accordance with good management
practice, and the charges for same shall be reasonable.

                  (iii) Landlord shall have the right at any time to install one
or more check meters in the Premises at Landlord's expense and to bill Tenant
for electrical consumption above seven watts per rentable square foot, at the
rate charged to Landlord by the utility company.

            (d) Cleaning. Landlord, at its expense, shall cause the Premises to
be cleaned, including the exterior and the interior of the windows thereof
(subject to Tenant maintaining unrestricted access to such windows), but
excluding any portions of the Premises used for the storage, preparation,
service or consumption of food or beverages. Tenant shall pay to Landlord,
Landlord's reasonable charges for any special or unusual cleaning work in the
Premises, including without limitation, the cleaning of private baths, interior
glass, pantries, kitchens, lounge areas, panelled and fabric walls, and wood
floors.

            (e) Security. In no event shall Landlord be required to provide any
security services to the Building. Tenant shall supply such security services to
the Premises as Tenant requires, subject to Landlord's prior approval of plans,
which shall not be unreasonably withheld.

            (f) Interruption of Services. Landlord does not warrant that any
service will be free from interruptions caused by repairs, renewals,
improvements, changes of service, alterations, strikes, lockouts, labor
controversies, accidents, inability to obtain fuel, water, or supplies, or other
cause beyond the reasonable control of Landlord. No such interruption of service
shall be deemed an eviction or disturbance of Tenant's use and possession of the
Demised Premises, or render Landlord liable to Tenant for damages by abatement
of Rent or otherwise, or relieve Tenant from performance of Tenant's obligations
under this Lease. Tenant hereby waives and releases all claims against Landlord
for damages for interruption or stoppage of service.

            Anything in this Lease to the contrary notwithstanding, if: (i) any
Essential Service (as defined below) is discontinued to the Premises for more
than seven consecutive business days; (ii) Tenant promptly gives Landlord notice
of such discontinuance; (iii) such discontinuance does not result from the
negligent or willful act or omission of Tenant or Tenant's employees or agents,
or from a requirement of Governmental Authority; and (iv) such discontinuance
renders any portion of the Premises untenantable shall thereupon abate until
such discontinuance is remedied. "Essential Service" means any of the following:
heating, ventilating, or cooling (as seasonally required), office electricity,
elevator service or plumbing services to the Premises. The abatement provided
for in this subsection shall not apply to any discontinuance of an Essential
Service caused by casualty or condemnation, which shall be governed respectively
by Section 15 and 16 herein. During any period in which the fee owner of the
Complex is any superior mortgagee or its affiliate claiming or succeeding to fee
title thereunder by foreclosure or deed in lieu of foreclosure of the successor
to such superior mortgagee, the provision for abatement in this paragraph shall
not be effective.
<PAGE>

                                        8


      13. INSURANCE. (a) Tenant shall, at its expense, secure and maintain
General Liability Insurance written on a so-called "Comprehensive" General
Liability Form with single limit coverage of at least $3,000,000, with no
deductible, naming Landlord as an additional insured under the policy. Tenant
shall deliver to Landlord duplicate certificates of such insurance prior to
taking occupancy of the Premises and shall delivery new certificates at least 30
days prior to the expiration of the existing coverage. Such certificates shall
provide that in the event of termination or material change in coverage,
Landlord shall be given ten days' advance notice in writing sent by certified
mail to the address of Landlord. Such insurance shall contain a waiver of the
insurer's right of subrogation against Landlord.

            (b) Landlord shall carry and maintain throughout the Term,
comprehensive "all-risk" fire and casualty insurance covering the Building and
other improvements on the Land in an amount necessary to avoid coinsurance, and
comprehensive general liability insurance coverage in amounts held by reasonably
prudent commercial landlords of comparable first-class office properties in the
City. Landlord shall maintain such insurance throughout the Term, subject to
changes in amounts which its institutional mortgagee(s) require.

            (c) Landlord and Tenant hereby waive all rights to recover against
each other for any loss or damage arising from any cost covered by any casualty
insurance required under the Lease, or otherwise actually carried by each of
them. Landlord and Tenant will diligently attempt to cause their respective
insurers to issue appropriate waiver of subrogation right endorsements to all
policies and insurance carried in connection with the Premises or the contents
of either of them. Landlord and Tenant hereby agree to look first to the
proceeds of their respective insurance policies before proceeding against each
other in connection with any claim relating to any matter covered by the Lease.

            (d) Notwithstanding the foregoing, Tenant shall be entitled to self
insure its insurance requirements as set forth in this Lease. Any self-insurance
shall be deemed to contain all of the terms and conditions applicable to such
insurance as required in this Lease, including, a full waiver of subrogation. If
Tenant elects to self-insure as aforesaid, with respect to any claims which may
result from incidents occurring during the term of this Lease, such
self-insurance obligation shall survive the expiration or earlier termination of
this Lease to the same extent as the insurance required hereunder would survive.

      14. SUBORDINATION. (a) This Lease is and shall be subject and subordinate
to (i) any and all mortgages now or hereafter affecting the fee title of the
Building, and to any and all present and future extensions, modifications,
renewals, replacements and amendments thereof; and (ii) any and all ground
leases now or hereafter affecting the Building or any part thereof and to any
and all extensions, modifications, renewals, replacements and amendments
thereof. Such subordination is subject to Landlord obtaining a non-disturbance
agreement from each mortgagee or ground lessor in the standard form used by such
party and which agreement shall provide, inter alia, that Tenant's occupancy of
the Premises shall not be disturbed so long as Tenant has and is performing all
of its obligations under this Lease, and in the case of a ground lessor, that
such ground lessor shall in no event have any rights with respect to Tenant and
this Lease other than rights held by Landlord, and
<PAGE>

                                        9


that such ground lessor cannot affect Tenant's rights under this Lease so long
as Tenant is performing all of its obligations under this Lease. Such agreement
shall not relieve the mortgagee or ground lessor from liability for payment of
the unpaid portion, if any, of the Allowance payable under Exhibit C hereto.

            Tenant will execute and deliver promptly to Landlord any reasonable
certificate or instrument which Landlord, from time to time, may request for
confirmation of the provisions of this Section.

            (b) Neither the foreclosure of a superior mortgage nor the
termination of a superior ground lease, nor the institution of any suit, action,
summary or other proceedings by Landlord or any successor landlord under such
ground lease or by the holder of any such mortgage, shall, by operation of law,
result in the cancellation or termination of the obligations of Tenant
hereunder, and Tenant agrees to attorn to and recognize Landlord and any
successor landlord under such ground lease or the holder of any such mortgage,
or the purchaser of the Building in foreclosure or any subsequent owner of the
fee, as the case may be, as Tenant's landlord hereunder in the event that any of
them shall succeed to Landlord's interest in the Premises.

      15. DESTRUCTION, FIRE OR OTHER CAUSES. (a) If the Premises or the Building
shall be partially damaged by fire or other casualty so that the damage can
reasonably be repaired by Landlord within 120 days from the date of the damage,
then the damage shall be diligently repaired by and at the expense of Landlord
(to the extent of net insurance proceeds received by Landlord for restoration),
subject to applicable laws and insurance requirements, and the Rent until such
repairs shall be apportioned according to the part of the Premises which is
tenantable.

            (b) If the Premises are destroyed or are rendered wholly
untenantable by fire or other cause, or are partially damaged so that the damage
cannot reasonably be repaired by Landlord within 120 days of the date of the
damage, or if the Building shall be so damaged that Landlord shall elect not to
restore the same but to demolish it or rebuild it, then in any of such events
Landlord may, within 45 days after such casualty, give Tenant a notice in
writing of intention to terminate this Lease, and thereupon the Term shall
expire, effective the date of the casualty, and Tenant shall vacate the Premises
and surrender the same to Landlord within a reasonable time after receipt of
Landlord's notice. If Landlord does not elect to terminate this Lease, the
provisions of subsection (a) shall govern.

            (c) Each of Landlord and Tenant hereby releases the other from any
and all liability or responsibility (to the releasor or anyone claiming through
or under the releasor by way of subrogation or otherwise) for any loss or damage
to property of the releasor, or anyone claiming through or under the releasor,
caused by fire or any of the extended coverage casualties, to the extent of
insurance proceeds received by the releasor.

            (d) Landlord shall not be liable for any damage to, or be required
(under any provision of this Lease or otherwise) to repair, restore or replace,
any property in the Premises or be liable to Tenant for damage arising from rain
or snow or from the bursting, overflowing or leakage of water,
<PAGE>

                                       10


steam or gas pipes or defect in the plumbing, HVAC, mechanical or electrical
systems of the Building, except for Landlord's negligence or breach of this
Lease, or from any act or neglect of any other tenant or occupant in the
Building.

      16. EMINENT DOMAIN. (a) If the whole of the Premises shall be acquired or
condemned by eminent domain for any public or quasi-public use or purpose, or if
any substantial part thereof of the Building is so acquired or condemned as to
render the Premises untenantable, or so that Landlord elects not to restore the
Building but to demolish or rebuild it, then and in that event, the Term shall
cease and terminate from the date of taking, Tenant shall have no claim against
Landlord or the condemning authority for the value of the unexpired Term, nor a
claim to any part of an award in such proceeding, and rent shall be adjusted and
paid to the date of such termination; provided, however, that Tenant may claim
against the authority for Tenant's moving costs and the value of Tenant's
property taken.

            (b) In the event of any other condemnation of a part of the Building
or Premises, this Lease shall remain in effect, but the Rent shall be prorated
based on that portion of the Premises which remains tenantable and Landlord
shall diligently repair the damage to the Building (to the extent of net
condemnation proceeds received by Landlord for restoration), subject to
applicable laws and insurance requirements.

      17. SUBLETTING. (a) Tenant shall not sublease all or any part of the
Premises, or suffer or permit the Premises or any part thereof to be subleased
to or used by others, without the prior written consent of Landlord in each
instance. If the Premises or any part thereof be sublet to or occupied by
anybody other than Tenant, Landlord may, at Landlord's option, collect rent from
the subtenant or occupant, and apply the net amount collected to the rent herein
reserved, but no such subletting, occupancy or collection shall be deemed a
waiver of this covenant, or the acceptance of the subtenant or occupants, or a
release of Tenant from the further performance by Tenant of covenants on the
part of Tenant herein contained. The consent by Landlord to sublet shall not be
construed to relieve Tenant from obtaining the express consent in writing of
Landlord to any further subletting.

            (b) If Tenant desires to sublease all or substantially all of the
Premises, Tenant shall first give notice to Landlord of the proposed transaction
and the term thereof, and Landlord shall have the right, by notice to Tenant
within 30 days after receipt of Tenant's notice, to terminate this Lease. If
Tenant desires to sublease less than substantially all of the Premises, Tenant
shall first give notice to Landlord as aforesaid, and Landlord shall have the
right to terminate this Lease with respect to the portion of the Premises
proposed to be subleased, as of the intended effective date of the proposed
sublease; provided however that upon receipt of a termination notice under this
sentence, Tenant may, by notice to Landlord within ten days thereafter, withdraw
its partial subleasing request, in which event the termination notice shall be
deemed rescinded. If Landlord exercises its right to terminate this Lease with
respect to such portion of the Premises, then (i) the Base Rent and Tenant's
Proportionate Share shall be proportionally reduced, and an adjustment shall be
made for amounts, if any, paid in advance and applicable to the portion of the
Premises no longer leased by Tenant, and (ii) the number of parking spaces
available for Tenant's use pursuant to Section 11 hereof shall be
<PAGE>

                                       11


proportionally reduced. If Landlord elects not to so terminate this Lease, then
Landlord shall not unreasonably withhold its consent to the proposed subletting.

            (c) Anything herein to the contrary notwithstanding, without
Landlord's prior consent but upon at least ten days' prior notice to Landlord,
Tenant may sublease part or all of the Premises to an entity, which controls, is
controlled by or under common control with Tenant, as the term "control" is
construed under the Federal securities laws.

      18. FEES AND EXPENSES. (a) If Tenant shall default in the observance or
performance of any term or covenant of this Lease, Landlord may, after ten days'
notice to Tenant to cure the default and failure of Tenant to cure the same
within such period, or at any time thereafter without notice in event of
emergency, perform the same for the account of Tenant. If Landlord makes any
expenditures or incurs any obligations in connection with a default by Tenant,
including, but not limited to, reasonable attorneys' fees in instituting,
prosecuting or defending any action or proceeding against Tenant, such sums paid
or obligations incurred, with interest (as provided below) and costs, shall be
deemed to be Additional Rent hereunder and shall be paid by Tenant to Landlord
within ten days of rendition of any bill or statement to Tenant hereunder.

            (b) Any Rent not paid by Tenant within 20 days after the due date
thereof, shall thereafter be payable with interest at the rate of 2% per annum
in excess of the prime or base rate of The Chase Manhattan Bank of Connecticut
(or its successor) in effect from time to time, from the due date to the date of
payment.

      19. NO REPRESENTATIONS BY LANDLORD, ETC. (a) Landlord and Landlord's
agents have made no representations or promises with respect to the Building or
the Premises, including the uses permitted under applicable law, except for
representations herein expressly set forth.

            (b) Tenant shall defend, indemnify and hold harmless Landlord, its
employees, agents and contractors against and from all liabilities, including
reasonable attorneys' fees, which may be imposed upon or incurred by or asserted
against Landlord or such other persons by reason of any of the following
occurring during the Term or prior thereto when Tenant has been given access to
the Premises: (i) any work or thing done in the Premises by or at the request of
Tenant, its employees or agents; (ii) any negligence or wrongful act or omission
of Tenant, its employees or agents; (iii) any accident, injury, loss or damage
to any person or property occurring in the Premises, except if due to the
negligence of Landlord, its employees or agents; and (iv) any failure on the
part of Tenant to comply with any of the terms of this Lease.

            (c) Any provision of this Lease which requires Landlord not to
unreasonably withhold its consent shall never be the basis for an award of
damages or give rise to a right of setoff or termination to Tenant, but may be
the basis for a declaratory judgment or specific injunction with respect to the
matter in question.
<PAGE>

                                       12


            (d) Tenant shall look solely to the estate and interest of Landlord,
its successors and assigns, in the Building for the collection of a judgment in
the event of a default by Landlord hereunder, and no other property or assets of
Landlord or any officer, director or partner of Landlord shall be subject to
levy, execution or other enforcement procedure for the satisfaction of Tenant's
remedies.

            (e) The failure of Landlord to insist in any one or more instances
upon the strict performance of any one or more of the agreements, terms,
covenants, conditions or obligations of this Lease, or to exercise any right,
remedy or election herein contained, shall not be construed as a waiver or
relinquishment for the future of the performance of such one or more obligations
of this Lease or of the right to exercise such election, but the same shall
continue and remain in full force and effect with respect to any subsequent
breach, act or omission, whether of a similar nature or otherwise.

            (f) Each party's obligations under this Lease shall survive the
Expiration Date or sooner termination of the Term, as same may be extended
hereunder.

            (g) The Building may be designated and known by any name Landlord
may choose, and such name or designation may be changed from time to time in
Landlord's sole discretion.

      20. QUIET ENJOYMENT. (a) Upon Tenant paying the Rent and observing and
performing all the terms, covenants and conditions on Tenant's part to be
observed and performed, Tenant may peaceably and quietly enjoy the Premises
hereby demised, free from any interference, molestation or acts of Landlord or
of anyone claiming by, through or under Landlord, subject, nevertheless, to the
terms and conditions of this Lease and to any ground lease and mortgages as
hereinbefore provided.

            (b) If Tenant retains possession of the Premises or any part thereof
after the Expiration Date or earlier termination date without the written
consent of Landlord, Tenant's occupancy shall be under all of the terms and
conditions of this Lease, except that (i) the tenancy shall be at will,
terminable by either party on ten days' written notice; (ii) the Base Rent shall
be equal to the greater of (x) 150% of the Base Rent payable at the termination
date, and (y) the then fair market rent for the Premises; and (iii) Tenant shall
indemnify and hold Landlord harmless for all damages sustained and liabilities
incurred by Landlord as a result of Tenant's continued occupancy beyond ten days
after Landlord's notice to Tenant under this subsection.

      21. DEFAULT. (a) If (i) Tenant defaults in the payment when due of any
installment of Rent, or (ii) Tenant defaults in fulfilling any other covenant of
this Lease and Tenant fails to remedy such default within 20 days after notice
by Landlord to Tenant specifying the nature of such default (or if the said
default cannot be completely cured or remedied within said 20-day period and
Tenant shall not have diligently commenced curing such default within such
20-day period and shall not thereafter in good faith diligently proceed to
remedy or cure such default), then Landlord may, by notice to Tenant, cancel
this Lease, and this Lease and the Term hereunder shall end and expire as fully
and completely as if the date of cancellation were the day herein definitely
fixed for the end and
<PAGE>

                                       13


expiration of this Lease and the Term hereof. Tenant shall then quit and
surrender the Premises to Landlord, but Tenant shall remain liable as
hereinafter provided.

            (b) If (i) the notice provided for in subsection (a) above shall
have been given and the Term shall expire as aforesaid, or (ii) Tenant shall
make default in payment of the Base Rent or any part of same or in making any
other payment herein provided for a period of ten days after notice by Landlord
to Tenant of such default, then and in any of such events, Landlord may, without
notice, re-enter the Premises, and dispossess Tenant, and the legal
representative of Tenant or other occupant of the Premises, by summary
proceedings or otherwise, and remove their effects and hold the Premises as if
this Lease had not been made, but Tenant shall remain liable for damages as
hereinafter provided.

      22. REMEDIES OF LANDLORD. In case of any such default, re-entry,
expiration and/or dispossess by summary proceedings or otherwise, (a) the Rent
shall become due thereupon and be paid up to the time of such re-entry,
dispossess and/or expiration, together with such expenses as Landlord may incur
for reasonable counsel fees, brokerage and/or putting the Premises in good
order, or for preparing the same for re-rental; (b) Landlord may re-let the
Premises or any part or parts thereof; either in the name of Landlord or
otherwise, for a term or terms, which may at Landlord's option be less than or
exceed the period which would otherwise have constituted the balance of the
Term, and may grant concessions of free rent; and/or (c) Tenant or the legal
representatives of Tenant shall also pay Landlord any deficiency between (i) the
Rent hereby reserved and/or covenanted to be paid, and (ii) the net amount, if
any, of the rents collected on account of the lease or leases of the Premises
for each month of the period which would otherwise have constituted the balance
of the Term. There shall be added to such deficiency such expenses as Landlord
may incur in connection with re-letting the Premises, including without
limitation, counsel fees, brokerage commissions and expenses incurred in
maintaining the Premises in good order and in connection with renovating and
preparing the same for re-letting. Any such rent deficiency shall be paid in
monthly installments by Tenant on the rent day specified in this Lease, and any
suit brought to collect the amount of the deficiency for any month shall not
prejudice in any way the rights of Landlord to collect the deficiency for any
subsequent month or months by a similar proceeding. In addition, Landlord shall
have the alternative of commencing suit against Tenant at any time for an amount
equal to the Rent reserved for the balance of the Term less the fair rental
value of the Premises for the same period. Landlord, at its option, may make
such alterations, repairs, replacements and/or decorations in the Premises as
Landlord considers advisable for the purpose of re-letting the Premises; and the
making of such alterations and/or decorations shall not operate or be construed
to release Tenant from liability hereunder as aforesaid. The failure of Landlord
to re-let the Premises or any part thereof shall not release or affect Tenant's
liability for continued rent or damages hereunder nor shall Landlord in any
event be liable in any way whatsoever for failure to re-let the Premises;
provided, however, that, to the extent required by Connecticut law, Landlord
shall make commercially reasonable efforts to re-let the Premises. In the event
of a breach by Tenant of any of the covenants or provisions hereof; Landlord
shall have the right of injunction and the right to invoke any remedy allowed at
law or in equity, as if re-entry, summary proceedings and other remedies were
not herein provided for. Mention in this Lease of any particular remedy shall
not preclude Landlord from any other remedy, in law or in equity.
<PAGE>

                                       14

      23. RIGHT TO EXHIBIT PREMISES AND ACCESS TO PREMISES. (a) Landlord
reserves the right to enter the Premises and exhibit same at any reasonable time
and upon reasonable notice (i) to prospective mortgagees, purchasers and ground
lessees, and (ii) to prospective tenants at any time within 180 days prior to
the expiration of the Term.

            (b) Landlord reserves the right to have its employees and agents
enter the Premises at any reasonable time (and at any time in case of emergency)
in order to gain access to any utility area, which utility area contains
equipment and systems for the Building, and in order to effect necessary repairs
and replacements.

            (c) Landlord shall exercise all access rights to the Premises
available under this Lease, in each instance, upon reasonable advance notice to
Tenant, in a manner consistent with Tenant's reasonable security requirements
and in a manner which does not unreasonably interfere with Tenant's business
operations, except in any event in case of emergency.

      24. RULES AND REGULATIONS. Tenant and Tenant's servants, employees,
agents, visitors, invitees and licensees shall observe faithfully and comply
strictly with such Rules and Regulations as Landlord's's agents may, from time
to time, adopt.

      25. BROKERAGE. Tenant warrants and represents it has not had or dealt with
any realtor, broker or agent in connection with the negotiation of this Lease,
except for the Broker, and agrees to pay and to hold Landlord harmless from any
cost, expense or liability (including costs of suit and attorneys' fees) for any
compensation, commission or charges claimed by any realtor, broker or agent with
respect to this Lease and the negotiation thereof, other than a claim of the
Broker and a claim based upon any written agreement between such person and
Landlord. Landlord represents that it has not entered into a written agreement
with any broker other than the Broker, with respect to the leasing of the
Building and which is in effect this date. Landlord shall indemnify and hold
Tenant harmless from any claim of the Broker (except for a claim based on an
agreement between Tenant and the Broker) and of any other broker with whom
Landlord has an agreement, all with respect to this Lease.

      26. FORCE MAJEURE. Landlord and Tenant, respectively, shall not be in
default hereunder if such party is unable to fulfill or is delayed in fulfilling
any of its obligations hereunder, including, without limitation, any obligations
to supply any service hereunder, or any obligations to make repairs or
replacements hereunder, if such party is prevented from fulfilling or is delayed
in fulfilling such obligations by reason of fire or other casualty, strikes or
labor troubles, governmental preemption-emption in connection with a national
emergency, shortage of supplies or materials, or by reason of any rule, order or
regulation of any governmental authority, or by reason of the condition of
supply and demand affected by war or other emergency, or any other cause beyond
its reasonable control. Such inability or delay by Landlord or Tenant in
fulfilling any of their respective obligations hereunder shall not affect,
impair or excuse the other party hereto from the performance of any of the
terms, covenants, conditions, limitations, provisions or agreements hereunder on
its part to be performed, nor result in any abatement of rents or Additional
Rents payable hereunder. Tenant shall not, however, be excused hereunder from
the prompt and full payment of Base Rent or Additional Rent for any cause
specified in this Section.
<PAGE>

                                       15


      27. SECURITY DEPOSIT. Tenant will deposit a security deposit with the
Landlord in the amount of $11,895.83, which is not to be applied toward the
tenant's rent.

      28. LEASE STATUS AND NOTICE. (a) Upon request of Landlord from time to
time, Tenant will execute and deliver to Landlord an instruments prepared by
Landlord stating, if the same be true, that this Lease is a true and exact copy
of the Lease between the parties hereto, that there are no amendments hereof (or
stating what amendments there may be), that the same is then in full force and
effect and that, to the best of Tenant's knowledge, there are then no offsets,
defenses or counterclaims with respect to the payment of rent reserved hereunder
or in the performance of the other terms, covenants and conditions hereof on the
part of the Tenant to be performed, and that as of such date no default has been
declared hereunder by either party hereto and that Tenant at the time has no
knowledge of any facts or circumstances which it might reasonably believe would
give rise to a default by either party. Such estoppel certificate required by
any party with whom Landlord is dealing may be in somewhat altered form from the
above terms.

            (b) Any notice, demand, consent, approval, directions, agreement or
other communication required or permitted hereunder or under any other documents
in connection herewith shall be in writing and shall be directed as follows:

      If to Landlord:   Principal Mutual Life Insurance Company
                        c/o Northeast Equity Asset Management Team
                        711 High Street
                        Des Moines, Iowa 50392

      With Copies to:   Servus Management Corporation
                        Manager for Principal Mutual Life Insurance Company
                        One Financial Plaza
                        Hartford, CT 06103

      If to Tenant:     Open Solutions, Inc.
                        300 Winding Brook Drive
                        Glastonbury, Connecticut 06033

      With a copy to:   N/A

or to such changed address or facsimile number as a party hereto shall designate
to the other parties hereto from time to time in writing. Notices shall be (i)
personally delivered (including delivery by Federal Express or other comparable
nation-wide overnight courier service) to the offices set forth above, in which
case they shall be deemed delivered on the date of delivery (or first business
day thereafter if delivered other than on a business day or after 5:00 p.m.
Eastern Standard Time to said offices); (ii) sent by certified mail, return
receipt requested, in which case they shall be deemed delivered on the date
shown on the receipt unless delivery is refused or delayed by the addressee in
which event they shall be deemed delivered on the date of deposit in the U. S.
Mail; or (iii) sent by means of a facsimile transmittal machine, in which case
they shall be deemed delivered at the time and
<PAGE>

                                       16


on the date of receipt thereof confirmed by telephonic acknowledgement on first
business day thereafter if receipted other than on a business day or after 5:00
p.m. Eastern Standard Time.

      29. ASSIGNS. The covenants, conditions and agreements contained in this
Lease shall bind and inure to the benefit of Landlord and Tenant and their
respective heirs, distributees, executors, administrators, successors and,
except as otherwise provided in this Lease, their assigns.

            The word Landlord as used in this Lease means only the owner for the
time being of Landlord's interest in this Lease. In the event of any assignment
of Landlord's interest in this Lease, the assignor in each case shall no longer
be liable for the performance or observance of any agreements or conditions on
the part of the Landlord to be performed or observed.

      30. OPTION TO EXTEND. (a) Tenant shall have one option to extend the Term
for an additional period of five years upon all of the terms and conditions of
this Lease, except that (i) the Base Rent during the extension Term shall be 95%
of the fair rental value of the Premises at the date three months prior to the
commencement of the extension Term; and (ii) there shall be no further option to
extend beyond the expiration of such extension Term.

            (b) Tenant's option may be exercised only by notice of exercise
given by Tenant to Landlord at least twelve months prior to the expiration of
the then current Term. Failure to so exercise within such period shall render
any subsequent attempted exercise void and of no effect, any principles of law
to the contrary not withstanding. Tenant shall have no right to exercise its
option to extend the Term, and any attempted exercise shall be void and of no
effect, if: (i) the named Tenant has assigned this Lease or has at any time
subleased, in the aggregate, more than 50% of the Premises to a party other than
one controlling, controlled by or under common control with Tenant; or (ii)
Tenant shall be in default hereunder and such default shall not have been cured
at the time of the attempted exercise or, if such default occurs after Tenant's
attempted exercise of the option, at the time of the proposed commencement of
the extension Term.

            (c) In the event that the parties have not agreed upon the fair
rental value of the Premises prior to the date three months before the
commencement of the extension Term, such value shall be determined by
arbitration in the City before a single arbitrator as follows:

                  (i) Landlord and Tenant shall have 15 days within which to
select one mutually agreeable arbitrator. If Landlord and Tenant fail to agree
on one arbitrator within the 15 day period, either party may promptly request
the president of the local Board of Realtors to appoint an arbitrator for the
matter, and said president's selection shall be binding upon Landlord and
Tenant. Said president shall appoint as arbitrator an individual with the
following qualifications: MAI credentials; ten years' experience in the business
of appraising commercial real estate; generally recognized competence in the
valuation of commercial rental properties in Hartford County; and has never been
a direct or indirect employee or agent of either Landlord or Tenant.

                  (ii) Landlord and Tenant shall each submit to the arbitrator,
in writing, a good faith determination of the fair rental value of the Premises.
<PAGE>

                                       17

                  (iii) The appraiser selected must choose either Landlord's or
Tenant's good faith determination of the fair rental value of the Premises and
the appraiser's choice shall be final and binding upon the parties. In
determining the fair rental value of the Premises and which of Landlord's or
Tenant's determinations to select, the appraiser shall consider all relevant
factors. From the date of appointment, the arbitrator shall have 30 days within
which to render a decision as to the fair rental value of the Premises. If the
arbitrator fails to render a decision within the applicable 30-day period,
either party shall have the right to apply to the American Academy of
Arbitrators for a decision.

            Judgement upon the award rendered by the arbitrator shall be binding
upon the parties and may be entered in any court of competent jurisdiction. The
arbitrator shall determine the liability of the parties for the costs of the
arbitration and may allocate counsel fees, witness fees and other costs between
the parties.

      31. EXPANSION OPTION. (a) If, at any time during the Term, any space
becomes available in the Building and if another tenant of the Building has not
exercised a superior right to lease such space, Landlord shall so notify Tenant
in writing and, provided that Tenant is not in default hereunder, Tenant shall
have the right, exercisable upon written notice give to Landlord within 15 days
after receipt of Landlord's notice, to lease such additional space (the
"Expansion Space") upon all the terms and conditions contained herein, except
that (i) Base Rent for the Expansion Space shall be the fair rental value of the
Expansion Space as of the date of Landlord's notice; and (ii) Tenant's
Proportionate Share shall be increased, based upon the ratio of the rentable
square footage of the Expansion Space to the rentable square footage of the
Building. Landlord's notice shall include a statement of Landlord's reasonable
estimate of the fair rental value of the Expansion space. If the parties have
not agreed upon the fair rental value of the Expansion Space at the time Tenant
exercises its option to lease same, such value shall be determined by
arbitration, as provided in Section 30 hereof.

      (b) If Tenant fails to exercise its option to lease the Expansion Space
within the 15-day period as set forth above, Landlord shall be free to lease the
Expansion Space to any party upon any terms and conditions Landlord shall
determine, from time to time during the Term, without any further obligation to
Tenant under the Section. Subsequent to Tenant's failure to exercise its option,
Tenant shall, within ten days after demand thereof by Landlord, confirm in
writing that Tenant has declined to exercise such right.

      (c) Tenant shall have no right to exercise its option to lease the
Expansion Space, and any attempted exercise shall be void and of no effect, if:
(i) the named Tenant has assigned this Lease or has at any time subleased, in
the aggregate, more than 50% of the Premises to a party other than one
controlling, controlled by or under common control with Tenant; or (ii) Tenant
shall be in default hereunder and such default shall not have been cured at the
time of the attempted exercise or, if such default occurs after Tenant's
attempted exercise of the option, at the time of the proposed commencement of
the lease of the Expansion Space.
<PAGE>

                                       18


      32. SIGNAGE. Tenant shall have the right to a listing in the lobby
directory of the Building and on the entrance door of the Premises. Tenant shall
have exterior signage on brick exterior or brick pedestal at the entrance, per
approval of the Town of Glastonbury and prior approval of Landlord.

      33. SEVERABILITY. Each covenant and agreement in this Lease shall be
construed to be a separate and independent covenant and agreement, and the
breach of any such covenant or agreement by Landlord shall not discharge or
relieve Tenant from Tenant's obligations to perform every covenant and agreement
of this Lease to be performed by Tenant. If any term of provision of this Lease
or any application thereof shall be invalid or unenforceable, the remainder of
this Lease and any other application of such term shall not be affected thereby.
The use of the term "herein" shall mean "in this Lease" unless the context
clearly indicates otherwise.

      34. SURRENDER OF PREMISES. At the expiration of the Term, Tenant will
peacefully yield up to Landlord the Premises, broom clean, in as good order and
repair as when delivered to Tenant, damage by fire, casualty and ordinary wear
and tear excepted. Any property left by Tenant in the Premises shall be deemed
abandoned by Tenant.

      35. GOVERNING LAW. This Lease shall be governed in all respects by the
laws of the State of Connecticut.

      36. LITIGATION EXPENSES. If any action, suit or proceeding is commenced
under or in connection with this Lease, the losing party shall pay to the
prevailing party, and the prevailing party shall be entitled to an award for,
attorneys' fees, court costs and other litigation expenses incurred by the
prevailing party in connection with such action, suit or proceeding.
<PAGE>

                                       19

      IN WITNESS WHEREOF, the parties hereto have hereunto set their hands and
seal the year and day first above written.


                                 LANDLORD:
                                 Principal Mutual Life Insurance Company
WITNESSES:                       an Iowa Corporation

/s/ Suzanne M. Baushouk          /s/ Michael S. Duffy     /s/ Ronald B. Franklin
-----------------------------    -----------------------------------------------

/s/ Marianne McCarty             Its:
-----------------------------    Michael S. Duffy         Ronald B. Franklin
                                 Assistant Director       Director
                                 Commercial Real Estate/  Commercial Real Estate
                                 Equities                 Loan Administration


WITNESSES:                       TENANTS:
                                 Open Solutions, Inc.

/s/ Katherine Holbrook           /s/ Clifford I. Waggoner
-----------------------------    -----------------------------------------------
                                 Clifford I Waggoner
                                 Vice President
-----------------------------


-----------------------------


-----------------------------    -----------------------------------------------
<PAGE>

                                    EXHIBIT A

                              [GRAPHIC: Floor Plan]
<PAGE>

                                    EXHIBIT B

                       LEGAL DESCRIPTION OF REAL PROPERTY

      A certain parcel of land situated in the Town of Glastonbury, County of
Hartford and State of Connecticut shown as lot No. 2 and 12' Right of Way on a
map filed in the Town Clerk's office in Glastonbury, Connecticut, titled: Salmon
Brook Corporate Park Subdivision Map, Glastonbury, Connecticut, sheet 1 of 3 No.
A-SI-59-S-1, scale 1" - 40', dated 1/12/82, rev. 8/3/82 by Luchs & Beckerman,
C.E.'s and also shown on a map to be filed in the Town Clerk's office in
Glastonbury, Connecticut, titled: Map prepared for Coeur d'Alene Development,
Inc., Glastonbury, Connecticut, No. A-84-60, scale 1" - 40', dated 7/18/84,.
rev. 9/17/84 by Luchs & Beckerman, C.E.'s to which maps reference is taken
herein, being more particularly bounded and described as follows:

      Beginning at a point on the southeasterly line of Winding Brook Drive on
the division line between land now or formerly of Amica Mutual Insurance Company
and the land described, said point being the northeasterly corner of the within
described parcel;

      thence running S10(degree) 27' 42"E 15.53 feet to a point, thence
S10(degree) 24' 36"E 673.51 feet to a point, and thence S80(degree)18' 27"W 7.84
feet, all along land now or formerly of said Amica Mutual Insurance Company, to
a point on the northerly line of Connecticut Route 94 also known as Hebron
Avenue;

      thence running in general westerly direction following an arc having a
radius of 1,004.93 feet and an interior angle of 3(degree) 32' 05", said arc
turning to the left, for a distance of 62.00 feet along said northerly line of
Connecticut Route 94 also known as Hebron Avenue to a point;

      thence running N54(degree) 46' 12"W 114.29 feet to a point, and thence in
general northwesterly direction following an arc having a radius of 1,044.00
feet and an interior angle of 16(degree) 23' 34", said arc turning to the left,
for a distance of 298.70 feet, all along northeasterly line of Connecticut Route
2, State of Connecticut o a point;

      thence running N19(degree) 21' 00"E 248.00 feet to a point, and thence
N10(degree) 33' 14"W 181.11 feet, all along lot No. 1, now or formerly of
Chinook Salmon Associates Limited Partnership, to a point on the southerly line
of Winding Brook Drive;

      thence running in general easterly direction following an arc having a
radius of 1,001.65 feet and an interior angle of 9(degree) 25' 10", said arc
turning to he left, for a distance of 164.67 feet to a point, and thence in
general northeasterly direction following an arc having a radius of 600.00 feet
at an interior angle of 9(degree) 37' 02", said arc turning to the left, for a
distance of 100.71 feet, all along said southerly and southeasterly line of
Winding Brook Drive to the point of beginning.
<PAGE>

                                    EXHIBIT C

                          TENANT IMPROVEMENT ALLOWANCE

      1. (a) Tenant shall, at Tenant's expense, submit to Landlord final and
complete dimensioned and detailed plans and drawings of partition layouts
(including openings, ceiling and lighting layouts, colors, mechanical and
electrical circuitry plans and any and all other information as may be
reasonably necessary to complete the construction of the Premises in accordance
with this Exhibit C (such plans are collectively referred to herein as "Tenant's
Plans"). The partition layout, and ceiling and lighting layout plans shall be
l'0" = 1/8" scale. Tenant shall submit Tenant's Plans and any other plans
required by this Exhibit C to Landlord in form, quality and quantity acceptable
for the purposes of filing for a building permit with the Building Department of
the City, and such plans shall be signed and sealed by an architect licensed in
the State of Connecticut;

            (b) Within ten days after receipt thereof, Landlord shall approve
Tenant's Plans or designate by notice to Tenant the specific changes required to
be made to Tenant's Plans. This procedure shall be repeated until Tenant's Plans
are finally approved by Landlord, which approval shall not be unreasonably
withheld or delayed.

            (c) All plans, drawings and specifications with respect to the
Premises required to be submitted by Tenant to Landlord shall comply with and
conform with the Building plans filed with the Department of Buildings and with
all the rules, regulations and/or other requirements of any governmental
department having jurisdiction over the construction of the Building and/or
Premises. Tenant shall prepare drawings in accordance with pre-existing
conditions and field measurements.

            (d) Landlord's review of Tenant's Plans is solely to protect the
interests of Landlord in the Building and the Premises, and Landlord shall be
neither the guarantor of, nor responsible for, the correctness or accuracy of
Tenant's Plans or the compliance of Tenant's Plans with applicable requirements
of Governmental Authority.

            (e) All visible office space from the building lobby must be
builtout and completed within the first three months of occupancy in a Class A
manner.

      2. (a) Tenant shall select a general contractor (the "Contractor"),
subject to the approval of Landlord, which approval will not be unreasonably
withheld and shall be granted within five business days of request for such
approval.

            The construction contract will require that before starting work,
the Contractor shall obtain and deliver to Landlord final and unconditional
waivers of mechanic's liens concerning the work for all labor and services to be
performed and all material to be furnished in connection with the work, signed
by the Contractor and all subcontractors, suppliers, and laborers to become
involved in the work.

            (b) Landlord shall provide Tenant access to the premises before the
commencement date for the purpose of tenant improvements.

            All provisions shall be in effect except rent which is not due
untile the commencement date.
<PAGE>

            (c) In the event that Tenant requests any changes to Tenant's Plans,
Landlord shall not unreasonably withhold its consent to any such changes,
provided the changes do not adversely affect the Building's structure, systems,
equipment or appearance.

            (d) The "Allowance" will be applied to the cost of construction of
the Tenant Improvements and for no other purpose. The Allowance shall be an
amount up of $16,880.00. Landlord shall pay Tenant $16,880.00 upon Tenant's
verification that Tenant paid at least $16,880.00 toward ceiling and lighting
retrofit.

      3. (a) All the Tenant Improvements shall be in accordance with the rules
and regulations of any governmental department or bureau having jurisdiction
thereover and shall not conflict with, or be in violation or cause any violation
of; Landlord's basic Building plans and/or the construction of the Building, and
all the Tenant Improvements shall be completed free of all liens and
encumbrances. All permits which may be required by Landlord for the Tenant
Improvements shall be procured and paid for by Tenant.

            (b) Upon completion of the Tenant Improvements, Tenant will remove
all debris and excess materials from the Building and the Premises.

            (c) In the event Tenant or the Contractor shall enter upon the
Premises or any other part of the Building, as may be permitted by Landlord,
Tenant shall indemnify and save Landlord free and harmless from and against any
and all claims arising from or out of any entry thereon or the performance of
the Tenant Improvements and from and against any and all claims arising from or
claimed to arise from any act or neglect of Tenant or Tenant's Representatives
or from any failure to act, or for any other reason whatsoever arising out of
said entry or such work. As a condition to Landlord's permission to Tenant to
make any of the Tenant Improvements in the Premises, Landlord may require that
Tenant agree with Landlord as to the fixing of the Commencement Date of this
Lease.

      4. Tenant accepts the Premises in its "as is" condition and acknowledges
that it has had an opportunity to inspect the Premises before executing this
Lease.
<PAGE>

                                    EXHIBIT D

                         BUILDING RULES AND REGULATIONS

                             300 WINDING BROOK DRIVE

            1. The sidewalks, entries, passages, court corridors, stairways and
elevators shall not be obstructed by Tenants, their employees or agents, or used
by them for purposes other than ingress and egress to and from their respective
suites.

            2. All safes or other heavy articles shall be carried up or into the
premises only at such times and in such manner as shall be prescribed by the
Landlord and the Landlord shall in all cases have the right to specify the
proper weight and position of any such safe or other heavy article. Any damage
done to the Building by taking in or removing any equipment or from overloading
any such safe or other heavy article. Any damage done to the Building by taking
in or removing any equipment or from overloading any floor in any way shall be
paid by the Tenant. Defacing or injuring in any way any part of the Building by
the Tenant, his invitees, agents or employees, shall be paid for by the Tenant.

            3. Tenant will refer all contractors, contractors' representatives
and installation technicians rendering any service to the premises for Tenant to
Landlord for Landlord's approval and supervision before performance of any
contractual service. This provision shall apply to all work performed in the
Building, including installation of telephones, telegraph equipment, electrical
devices and attachments and installations of any nature affecting floors, walls,
woodwork, trim, windows, ceilings, equipment or any other physical portion of
the Building. Such approval, if given, shall in no way make Landlord, a party to
any contract between Tenant and any such contractor, and Landlord shall have no
liability therefor.

            4. No sign, advertisement or notice shall be inscribed, painted, or
affixed on any part of the inside or outside of the Building unless of such
color, size and style and in such place as shall first be designated by
Landlord, there shall be no obligation or duty on Landlord to allow any sign,
advertisement or notice to be inscribed, painted or affixed on any part of the
inside or outside of the Building. Tenant suite identification on or adjacent to
entry doors will conform to standards established by Landlord and must be
installed by Landlord at Tenant's expense. A directory in a conspicuous place,
with the names of the Tenants, will be provided by Landlord, any necessary
revision in Tenant's name shall be made by Landlord within a reasonable time
after notice from the Tenant, and upon payment of a standard fee. No furniture
shall be placed in front of the Building or in any lobby or corridor without
written consent of Landlord. Landlord shall have the right to remove all other
signs and furniture, without notice to Tenant at the expense of Tenant.

            5. Tenant shall have the non-exclusive use in common with the
Landlord, other tenants, their guests and invitees, of the automobile parking
areas, driveways and footways, subject to reasonable rules and regulations for
the use thereof as prescribed from time to time by Landlord. Landlord shall have
the right to designate parking areas for the use of the building tenants and
their
<PAGE>

employees, and the tenants and their employees shall not park in parking areas
not so designated, specifically including driveways, fire lanes,
loading/unloading areas, walkways and building entrances. Tenant agrees that
upon written notice from Landlord, it will furnish to Landlord, within five (5)
days from receipt of such notice, the state automobile license numbers assigned
to the automobiles of the Tenant and its employees. Landlord shall not be liable
for any vehicle of the Tenant or its employees that the Landlord shall have
towed from the premises when illegally parked. Landlord will not be liable for
damage to vehicles in the parking areas or for theft of vehicles, personal
property from vehicles, or equipment of vehicles. Tenant agrees that Tenant and
employees of Tenant shall not park on off-site surrounding property, whether
publicly or privately owned, without the written consent of the owner of such
surrounding property.

            6. No Tenant shall do or permit anything to be done in said
premises, or bring or keep anything therein, which will in any way increase the
rate of fire insurance on said Building, or on property kept therein, or
obstruct or interfere with the rights of other Tenants, or in any way injure or
annoy them, or conflict with the laws relating to fire, or with any regulations
of the fire department, or with any insurance policy upon said buildings or any
part thereof, or conflict with any rules and ordinances of the local Board of
Health or any governing bodies.

            7. The janitor of the Building may at all times keep a pass key, and
he and other agents of the Landlord shall at all times be allowed admittance to
said Demised Premises.

            8. No additional locks shall be placed upon any doors without the
written consent of the Landlord. All keys to the Demised Premises and the
Building Security Card Keys (if any) shall be furnished by the Landlord in a
reasonable number commensurate with the square footage leased. Additional keys
and Building Security Card Keys (if any) shall be furnished at Tenant cost. Upon
termination of this lease, all keys and Building Security Card Keys (if any)
shall be surrendered, and the Tenant shall then give the Landlord or his agents
explanation of the combination of all locks upon the doors and vaults.

            9. No windows or other openings that reflect or admit light into the
corridors or passageways, or to any other place in said Building, shall be
covered or obstructed by any of the Tenants.

            10. No person shall disturb the occupants of the Building by the use
of any musical instruments, radios, televisions, phonographs, tape players,
etc., the making of unreasonable noises, odors, vibrations or any other
unreasonable use of the Building. No dogs or other animals or pets of any kind
will be allowed in the Building.

            11. The water closets and other fixtures shall not be used for any
purpose other than those for which they were constructed, and any damage
resulting to them from misuse, or the defacing or injury of any part of the
Building, shall be borne by the person who shall occasion it.

            12. No bicycles or similar vehicles will be allowed in the Building.

            13. Nothing shall be thrown out the windows of the Building or down
the stairways
<PAGE>

or other passages.

            14. Tenant shall not be permitted to use or to keep in the Building
any flammable or explosive materials.

            15. If any Tenant desires, at his cost, telegraphic, telephonic, or
other electric connections, Landlord or its agents will direct the electricians
(which must be approved in advance by Landlord) as to where and how the wires
may be introduced, and without such directions, no boring or cutting for wires
will be permitted.

            16. If Tenant desires shades, draperies or other window treatment,
they must be of such shape, color, material and make as shall conform with other
window treatment within the Building, shall be purchased and installed at the
sole cost and expense of Tenant, and shall be approved in advance by Landlord.

            17. Landlord or its agents shall have the right to enter the
premises to examine the same or to make such repairs, alterations or additions
as Landlord shall deem necessary for the safety, preservation or improvement of
the Building.

            18. Landlord or its agents may show said premises and may place on
the windows or doors thereof; or upon the bulletin board, a notice "For Rent"
for six (6)months prior to the expiration of the lease.

            19. All glass, locks and trimmings in or about the doors and windows
and all electric fixtures belonging to the Building shall be kept whole, and
whenever broken shall be immediately replaced or repaired by Landlord at the
sole cost and expense of Tenant.

            20. Tenant shall not install or authorize the installation of any
vending machines, food or beverage preparation machines or dispensing devices,
nor shall Tenant authorize the delivery of food or beverage to the Building,
without Landlord's prior written approval. Landlord shall have the right to
rescind this approval, if given, without liability to Tenant for reimbursement
of any Tenant costs or expenses.

            21. Landlord reserves the right at any time to take one elevator out
of service to Tenants for exclusive use by the Building management in servicing
the Building.

            22. No cooking shall be done or permitted by any tenant on the
Demised Premises, nor shall the Demised Premises be used for the storage of
merchandise, for washing clothes, for lodging, or for any unlawful, improper,
objectionable or immoral purpose.

            23. Tenant shall not disturb any occupant of the Building, or canvas
or conduct surveys within the Building (without the prior written consent of
Landlord), and shall cooperate to prevent same.

            24. Landlord reserves the right to exclude or expel from the
Building any person
<PAGE>

                            FIRST AMENDMENT TO LEASE

      This FIRST AMENDMENT TO LEASE (this "Amendment"), is dated as of January
27, 1998, by and between PRINCIPAL MUTUAL LIFE INSURANCE COMPANY, an Iowa
corporation having an office at 711 High Street, Des Moines, Iowa ("Landlord"),
and OPEN SOLUTIONS, INC. a Connecticut corporation having an office at 300
Winding Brook Drive, Glastonbury, Connecticut ("Tenant').

                                     R E C I T A L S:

      A. Pursuant to a certain Lease dated February 29, 1996 (the "Lease"),
between Landlord and Tenant, Landlord leased to Tenant certain space in the
building located at 300 Winding Brook Drive, Glastonbury, Connecticut (the
"Property").

      B. Landlord has agreed to expand the parking area at the Property, and
Tenant has agreed to bear its proportionate cost of such expansion by agreeing
to increase its existing Annual Base Rent (as defined in the Lease). In
consideration therefor, Tenant shall be permitted to use the expansion parking
area in accordance with the terms of the Lease.

      C. Landlord and Tenant wish to amend the Lease to provide for such
increase in Annual Base Rent, all as more particularly provided herein.

      NOW, THEREFORE, in consideration of the mutual covenants and promises
contained herein and in the Lease, Landlord and Tenant agree as follows:

      1. Amendments to Lease, Effective as of November 1, 1997, Landlord and
Tenant hereby amend the Lease as follows:

      (a) The following definition of "Additional Parking Rent" is added to the
Lease as Section 2(vii):

      (vii) Additional Parking Rent:

       Period             Annual Additional Parking Rent  Monthly Installment
       ------             ------------------------------  -------------------

       December 1, 1997-  $2,569.50                       $214.13
       November 1, 2002
<PAGE>

      (b) The following language is added to the end of Section 5:

      Tenant shall pay to Landlord Additional Parking Rent without demand and
      without setoff or deductions of any kind, in the monthly installments set
      forth in Section 2(vii), in advance, on the first day of each calendar
      month of the Term commencing on the first to occur of (i) December 1,1997,
      or (ii) the Additional Parking Completion Date (as defined below), in
      either case, at the address of Landlord stated above or such other place
      as Landlord may designate in writing from time to time. In the event of
      the termination of the Term prior to November 1, 2002, all unpaid
      installments of Additional Parking Rent shall become immediately due and
      payable. For purposes of this Lease, the "Additional Parking Completion
      Date" shall mean the date on which the 42-space addition to the existing
      parking area at the Property is substantially completed and available for
      use by Tenant. If the Additional Parking Commencement Date shall be any
      day other than the first day of a calendar month, then, Tenant shall pay
      Additional Parking Rent for such calendar month prorated on a per diem
      basis, and the final payment of Additional Parking Rent shall be reduced
      by the amount of such prorated payment.

      2. Miscellaneous.

      (a) Except as expressly provided herein, nothing in this Amendment shall
be deemed to waive or modify any of the provisions of the Lease. In the event of
any conflict between the terms of the Lease and this Amendment, the terms of
this Amendment shall prevail. Except as amended specifically by this Amendment,
all of the terms, covenants and conditions of the Lease shall remain unmodified
and in full force and effect, and are hereby ratified and affirmed by Landlord
and Tenant.

      (b) This Amendment shall be binding upon and inure to the benefit of the
heirs, executors, administrators, successors and assigns of the respective
parties thereto.

      (c) All terms capitalized herein and not defined herein shall have the
meanings ascribed to such terms in the Lease.

      (d) This Amendment may be executed in several counterparts, each of which
may be deemed an original, but all of which together shall constitute one and
the same agreement.

      (e) The recitals set forth at the beginning of this Amendment and the
schedules attached hereto are incorporated in and made a part of this Amendment
by this reference.

      (f) Landlord and Tenant each represent and warrant that they have the
authority to enter into this Amendment without the consent, joinder or approval
of any other party.

           (Remainder of Page Intentionally Left Blank; Signature Page Follows)


                                        2
<PAGE>

      IN WITNESS WHEREOF, Landlord and Tenant have caused this Amendment to be
duly executed as of the day and year first written above.

Witnesses:                             LANDLORD:

                                       PRINCIPAL MUTUAL LIFE INSURANCE COMPANY


/s/ Katie M. Michael                   By: /s/ Scott D. Harris
------------------------------             ------------------------------------
                                       Name: Scott D. Harris
                                       Title: Assistant Director
                                              Commercial Real Estate/Equities

/s/ [Illegible]                        By: /s/ R. L. Minear
------------------------------             ------------------------------------
                                       Name: R. L. Minear
                                       Title: Director
                                              Corporate Real Estate
------------------------------
                                       TENANT:

Witnesses:                             OPEN SOLUTIONS, INC.


/s/ [Illegible]                        By: /s/ Debra M. Dubrowski
------------------------------             ------------------------------------
                                       Name: Debra M. Dubrowski
                                       Title: Controller
------------------------------


                                        3
<PAGE>

STATE OF IOWA   )
                ) ss. Des Moines
COUNTY OF       )

      On this the 27th day of January, 1998, before me, Susan Wieland, the
undersigned officer, personally appeared Scott D. Harris, who acknowledged
himself to be the Asst. Director of PRINCIPAL MUTUAL LIFE INSURANCE COMPANY, a
corporation, and that he/she, in such capacity being authorized so to do
executed the foregoing instrument as his/her free act and deed and the free act
and deed of the corporation for the purposes contained therein by signing the
name of such corporation by himself/herself as such officer.

      IN WITNESS WHEREOF, I hereunto set my hand.


                                          /s/ Susan Wieland
                                          ------------------------------
                                          Notary Public
                                          My Commission expires: _______
                                          [Affix Notarial Seal]

                                          [LOGO] SUSAN WIELAND
                                                 MY COMMISSION EXPIRES
                                                 July 28, 2000
STATE OF IOWA   )
                ) ss. Des Moines
COUNTY OF       )

      On this the 27th day of January, 1998, before me, Susan Wieland, the
undersigned officer, personally appeared R.L. Minear, who acknowledged himself
to be the Director of PRINCIPAL MUTUAL LIFE INSURANCE COMPANY, a corporation,
and that he/she, in such capacity being authorized so to do executed the
foregoing instrument as his/her free act and deed and the free act and deed of
the corporation for the purposes contained therein by signing the name of such
corporation by himself/herself as such officer.

      IN WITNESS WHEREOF, I hereunto set my hand.


                                          /s/ Susan Wieland
                                          ------------------------------
                                          Notary Public
                                          My Commission expires: _______
                                          [Affix Notarial Seal]

                                          [LOGO] SUSAN WIELAND
                                                 MY COMMISSION EXPIRES
                                                 July 28, 2000


                                        4
<PAGE>

STATE OF        )
                ) ss.
COUNTY OF       )


      On this the ___ day of _____________,1997, before me, ________________ the
undersigned officer, personally appeared ______________________ who acknowledged
himself/herself to be the _____________________________ of OPEN SOLUTIONS, INC.
a Connecticut corporation, and that he/she, in such capacity being authorized so
to do, executed the foregoing instrument as his/her free act and deed and the
free act and deed of such corporation for the purposes contained therein by
signing the name of the partnership by himself/herself as such
_________________________

      IN WITNESS WHEREOF, I hereunto set my hand.

                                       ____________________________________
                                       Commissioner of the Superior Court
                                       Notary Public
                                       My Commission expires:_________
                                       [Affix Notarial Seal]


                                        5
<PAGE>

                            SECOND AMENDMENT TO LEASE

      This SECOND AMENDMENT TO LEASE (this "Amendment"), is dated as of May 25,
1999, by and between PRINCIPAL LIFE INSURANCE COMPANY, formerly known as
Principal Mutual Life Insurance Company, an Iowa corporation, having an address
at c/o Principal Capital Management, LLC, 801 Grand Avenue, Des Moines, Iowa
50392-1450 ("Landlord"), and OPEN SOLUTIONS, INC. a Connecticut corporation
having an office at 300 Winding Brook Drive, Glastonbury, Connecticut
("Tenant").

                                    RECITALS:

      A. Pursuant to a certain Lease dated February 29,1996, as amended by First
Amendment to Lease dated July 1, 1998 (the "Lease"), between Landlord and
Tenant, Landlord leased to Tenant certain space consisting of approximately
14,275 rentable square feet in the first floor of the building (the "Original
Space") located at 300 Winding Brook Drive, Glastonbury, Connecticut (the
"Property").

      B. Landlord and Tenant wish to amend the Lease to increase the size of the
leased premises and in certain other particulars.

      NOW, THEREFORE, in consideration of the mutual covenants and promises
contained herein and in the Lease, Landlord and Tenant agree as follows:

      1. Additional Space. In addition to the Original Space leased to Tenant
under the Lease, Landlord hereby leases to Tenant and Tenant hereby leases from
Landlord effective as of August 1, 1999, for the terms and upon the rentals set
forth in the Lease, except as otherwise set forth in this Second Amendment, the
premises consisting of approximately 3,032 rentable square feet on the second
(2nd) floor of the Property (the "Additional Space") as shown on Exhibit A-1
attached hereto and made a part hereof. Tenant agrees to accept the Additional
Space as is, in the condition presently existing, and Landlord shall have no
obligation to make any repairs, alterations or improvements with respect to the
Additional Space.

      2. Space Layout. The Lease is hereby amended to add Exhibit A-1 to Exhibit
A of the Lease so that all references in the Lease to Exhibit A shall be deemed
to be references to Exhibit A and Exhibit A-1.

      3. Premises. The definition of "Premises" set forth in Paragraph 1. of the
Lease is hereby amended to include for all purposes the Original Space and the
Additional Space.

      4. Additional Space Rent. The following definition of "Additional Space
Rent" is added to the Lease as Paragraph 2, Section (vii):

            (vii) Additional Space Rent:

            Period             Annual Additional Space Rent  Monthly Installment
            ------             ----------------------------  -------------------

            August 1, 1999 -   $57,608.00                    $4,800.67
            April 30, 2003
<PAGE>

      5. Rent. All references to Base Rent in the Lease and herein shall for all
purposes include Additional Space Rent (so that Base Rent, Additional Space
Rent, Additional Rent and every other amount payable by Tenant under the Lease
and hereunder shall be collectively referred to as "Rent").

      6. Tenant's Proportionate Share. The Tenant's Proportionate Share as
defined in Section 2 (iii) of the Lease is hereby amended to be 56.04% for the
purpose of determining the Additional Rent under the Lease and for every other
purpose. The Tax Base Year and the Base Year with respect to the Additional
Space shall be the same as for the Original Space.

      7. Effective Date. The amendments and agreements set forth in Sections 1
through 7 above shall be effective as of August 1, 1999.

      8. Term. The term for the Additional Space shall commence on August 1,
1999 and shall expire on the Expiration Date (April 30, 2003).

      9. Brokerage. Section 25 of the Lease is hereby amended by the addition of
the following: For the purpose of the Second Amendment and the leasing of the
Additional Space, the reference to Broker in this Section 25 shall mean Servus
Brokerage Company, LLC.

      10. Miscellaneous.

            (a) Except as expressly provided herein, nothing in this Amendment
shall be deemed to waive or modify any of the provisions of the Lease. In the
event of any conflict between the terms of the Lease and this Amendment, the
terms of this Amendment shall prevail. Except as amended specifically by this
Amendment, all of the terms, covenants and conditions of the Lease shall remain
unmodified and in full force and effect, and are hereby ratified and affirmed by
Landlord and Tenant.

            (b) All terms capitalized herein and not defined herein shall have
the meanings ascribed to such terms in the Lease.

            (c) This Amendment may be executed in several counterparts, each of
which may be deemed an original, but all of which together shall constitute one
and the same agreement.

            (d) The recitals set forth at the beginning of this Amendment and
the schedules attached hereto are incorporated in and made a part of this
Amendment by this reference.

            (e) Landlord and Tenant each represent and warrant that they have
the authority to enter into this Amendment without the consent, joinder or
approval of any other party.

            (f) This Amendment shall be binding upon and inure to the benefit of
the heirs, executors, administrators. successors and assigns of the respective
parties thereto.


                                        2
<PAGE>

       IN WITNESS WHEREOF, Landlord and Tenant have caused this Amendment to be
duly executed as of the day and year first written above.

Witnesses:                         LANDLORD:

                                   PRINCIPAL LIFE INSURANCE COMPANY,
                                   an Iowa corporation

                                   By:   Principal Capital Management, LLC, a
                                         Delaware limited liability company, its
                                         authorized signatory


/s/ Judy Cline                           By: /s/ George Vogt Jr.
-------------------------------              --------------------------------
Name:                                        Name: Jay Vogt
                                             Its:  Vice President
/s/ [Illegible]                                    Equity Asset Management
-------------------------------
Name:


                                         By:
-------------------------------              --------------------------------
Name:                                        Name:
                                             Its:

                                   TENANT:

Witnesses:                         OPEN SOLUTIONS, INC.


/s/ Kathleen H. Callahan                 By: /s/ John L. Person
-------------------------------              --------------------------------
Name: Kathleen H. Callahan                   Name: John L. Person
                                             Its: President


/s/ Lauren S. Wright
-------------------------------
Name: Lauren S. Wright


-------------------------------


                                        3
<PAGE>

STATE OF IOWA      )
                   ) ss. Des Moines
COUNTY OF Polk     )

      On this the 16 day of June, 1999, before me, Nancy S. Niece, the
undersigned officer, personally appeared George Vogt, Jr., who acknowledged
himself/herself to be the Vice President of Principal Capital Management, LLC, a
Delaware limited liability company, authorized signatory of PRINCIPAL LIFE
INSURANCE COMPANY, an Iowa corporation, and that he/she, in such capacity being
authorized so to do, executed the foregoing instrument as his/her free act and
deed and the free act and deed of the limited liability company for the purposes
contained therein by signing the name of such limited liability company by
himself/herself as such officer.

      IN WITNESS WHEREOF, I hereunto set my hand.

                                          /s/ Nancy S. Niece
                                          ------------------------------

                                          [Affix Notarial Seal]
                                          Notary Public

                                          [LOGO] NANCY S. NIECE
                                                 MY COMMISSION EXPIRES
                                                 June 23, 2001
STATE OF IOWA      )
                   ) ss. Des Moines
COUNTY OF          )

      On this the ___ day of __________, 1999, before me, ________________, the
undersigned officer, personally appeared _____________________, who acknowledged
himself/herself to be the _______________ of Principal Capital Management, LLC,
a Delaware limited liability company, authorized signatory of PRINCIPAL LIFE
INSURANCE COMPANY, an Iowa corporation, and that he/she, in such capacity being
authorized so to do, executed the foregoing instrument as his/her free act and
deed and the free act and deed of the limited liability company for the purposes
contained therein by signing the name of such limited liability company by
himself/herself as such officer.

      IN WITNESS WHEREOF, I hereunto set my hand.


                                          ------------------------------

                                          [Affix Notarial Seal]
                                          Notary Public



                                        4
<PAGE>

STATE OF Connecticut   )
                       ) ss. Glastonbury
COUNTY OF Hartford     )

      On this the 25th day of May, 1999, before me, Kathleen H. Callahan, the
undersigned officer, personally appeared John L. Person, who acknowledged
himself to be the President of OPEN SOLUTIONS, INC. a Connecticut corporation,
and that he, in such capacity being authorized so to do, executed the foregoing
instrument as his free act and deed and the free act and deed of such
corporation for the purposes contained therein by signing the name of the
partnership by himself as such President.

      IN WITNESS WHEREOF, I hereunto set my hand.

                                 /s/ Kathleen H. Callahan
                                 ------------------------------
                                 Commissioner of the Superior Court
                                 Notary Public  My Commission Exp. Oct. 31, 2000
                                 My Commission expires: ______________
                                 [Affix Notarial Seal]


                                        5
<PAGE>

                                   EXHIBIT A-1

                                ADDITIONAL SPACE


                                  Exhibit A-1-1
<PAGE>

                                  EXHIBIT "A"-1

                              [GRAPHIC: Floor Plan]
<PAGE>

                                                                            COPY

                            THIRD AMENDMENT TO LEASE

      This THIRD AMENDMENT TO LEASE (this "Amendment"), is dated September 16,
1999, by and between FOSTER PROPERTIES, LLC, a Connecticut Limited Liability
Company, having an address at 100 Western Boulevard, Glastonbury, Connecticut.
06033 ("Landlord"), and OPEN SOLUTIONS, INC. a Connecticut corporation having an
office at 300 Winding Brook Drive, Glastonbury, Connecticut, 06033 ("Tenant").

                                    RECITALS:

      A. Pursuant to a certain Lease dated February 29, 1996, as amended by
First Amendment to Lease dated July 1, 1998, as amended by Second Amendment to
Lease dated May 25, 1999 (the "Lease"), between Landlord and Tenant, Landlord
leased to Tenant certain space consisting of approximately 14,275 rentable
square feet on the first floor of the building (the "Original Space") and
additional space consisting of approximately 3,032 rentable square feet on the
second floor of the building (the "First Additional Space") located at 300
Winding Brook Drive, Glastonbury, Connecticut (the "Property").

      B. Landlord and Tenant wish to amend the Lease to increase the size of the
leased premises and in certain other particulars.

      NOW, THEREFORE, in consideration of the mutual covenants and promises
contained herein and in the Lease, Landlord and Tenant agree as follows:

      1. Additional Space. In addition to the Original Space and the First
Additional Space leased to Tenant under the Lease, and its amendments, Landlord
hereby leases to Tenant and Tenant hereby leases from Landlord effective as of
November 1, 1999, for the terms and upon the rentals set forth in the Lease,
except as otherwise set forth in this Third Amendment, the premises consisting
of approximately 3,240 rentable square feet and 1,128 rentable square feet on
the second (2nd) floor of the Property (the "Second Additional Space") as shown
on Exhibit A-2 attached hereto and made a part hereof. Tenant agrees to accept
the Additional Space as is, in the condition presently existing, and Landlord
shall have no obligation to make any repairs, alterations or improvements with
respect to the Second Additional Space.

      2. Space Layout. The Lease is hereby amended to add Exhibit A-2 to Exhibit
A of the Lease and Exhibit A-1 of the Second Amendment To Lease, so that all
references in the Lease to Exhibit A, shall be deemed to be references to
Exhibit A, Exhibit A-1, and Exhibit A-2.

      3. Premises. The definition of "Premises" set forth in Paragraph 1. of the
Lease is hereby amended to include for all purposes the Original Space, the
First Additional Space and the Second Additional Space.
<PAGE>

      4. Additional Space Rent. The following definition of "Second Additional
Space Rent" is added to the Lease as Paragraph 2, Section (vii):

            (vii) Second Additional Space Rent:

Period               Annual Second Additional Rent  Monthly Installment
------               -----------------------------  -------------------
January 1, 2000 -    $82,992.00                     $6,916.00
April 30, 2003

      5. Rent. All references to Base Rent in the Lease and herein shall for all
purposes include Second Additional Space Rent (so that Base Rent, First
Additional Space Rent, Second Additional Space Rent, Additional Rent and every
other amount payable by Tenant under the Lease and hereunder shall be
collectively referred to as "Rent").

      6. Tenant's Proportionate Share. The Tenant's Proportionate Share as
defined in Section 2 (iii) of the Lease is hereby amended to be 70.19% for the
purpose of determining the Additional Rent under the Lease and for every other
purpose. The Tax Base Year and the Base Year with respect to the Additional
Space shall be the same as for the Original Space and First Additional Space.

      7. Effective Date. The amendments and agreements set forth in Sections 1
through 7 above shall be effective as of November 1, 1999.

      8. Term. The Term for the Additional Space shall commence on November 1,
1999 and shall expire on the Expiration Date (April 30, 2003).

      9. Brokerage. Section 25 of the Lease is hereby amended by the addition of
the following: For the purpose of the Third Amendment and the leasing of the
Additional Space, the reference to Broker in this Section 25 shall mean Servus
Brokerage Company, LLC.

      10. Miscellaneous.

            (a) Except as expressly provided herein, nothing in this Amendment
            shall be deemed to waive or modify any of the provisions of the
            Lease. In the event of any conflict between the terms of the Lease
            and this Amendment, the terms of this Amendment shall prevail.
            Except as amended specifically by this Amendment, all of the terms,
            covenants and conditions of the Lease shall remain unmodified and in
            full force and effect, and are hereby ratified and affirmed by
            Landlord and Tenant.

            (b) All terms capitalized herein and not defined herein shall have
            the meanings ascribed to such terms in the Lease.
<PAGE>

            (c) This Amendment may be executed in several counterparts, each of
            which may be deemed an original, but all of which together shall
            constitute one and the same agreement.

            (d) The recitals set forth at the beginning of this Amendment and
            the schedules attached hereto are incorporated in and made a part of
            this Amendment by this reference.

            (e) Landlord and Tenant each represent and warrant that they have
            the authority to enter into this Amendment without the consent,
            joinder or approval of any other party.

            (f) This Amendment shall be binding upon and inure to the benefit of
            the heirs, executors, administrators, successors and assigns of the
            respective parties thereto.

IN WITNESS WHEREOF, Landlord and Tenant have caused this Amendment to be duly
executed as of the day and year first written above.

Witnesses:                                LANDLORD:

                                          FOSTER PROPERTIES, LLC.
                                          a Connecticut Limited Liability
                                          Company

___________________________               By:______________________
Name:                                          Name:
                                               Its:

___________________________
Name:
                                          TENANT:
Witnesses:                                OPEN SOLUTIONS, INC.


/s/ Lauren S. Wright                      By: /s/ Jack Person
-------------------------------               -----------------------------
Name: Lauren S. Wright 9-16-99                Name: Jack Person
                                              Its: President


/s/ Debra Dubrowski Rooney
-------------------------------
Debra Dubrowski Rooney


<PAGE>

STATE OF CONNECTICUT               )
                                   )     ss. Glastonbury
COUNTY OF HARTFORD                 )

      On this the _____ day of ____________, 1999, before me,
_____________________, the undersigned officer, personally appeared
_____________________________, who acknowledged himself to be the
___________________________ of Foster Properties, LLC, a Connecticut limited
liability company, and that he, in such capacity being authorized so to do,
executed the foregoing instrument as his free act and deed and the free act and
deed of the limited liability company for the purposes contained therein by
signing the name of such limited liability company by himself as such officer.

      IN WITNESS WHEREOF, I hereunto set my hand.


                                         __________________________
                                         [Affix Notarial Seal}
                                         Notary Public

STATE OF CONNECTICUT               )
                                   )     ss. Glastonbury
COUNTY OF HARTFORD                 )

      On this the _____ day of ____________, 1999, before me,
_____________________, the undersigned officer, personally appeared
_____________________________, who acknowledged himself to be the
___________________________ of Open Solutions Inc., a Connecticut Corporation,
and that he, in such capacity being authorized so to do, executed the foregoing
instrument as his free act and deed and the free act and deed of the limited
liability company for the purposes contained therein by signing the name of such
limited liability company by himself as such officer.


                                         __________________________
                                         [Affix Notarial Seal)
                                         Notary Public
<PAGE>

                                   Exhibit A-2
                                    2nd Floor
                             300 Winding Brook Drive

                              [GRAPHIC: Floor Plan]