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                                                                    EXHIBIT 10.4

                               OPEN SOLUTIONS INC.

                        2003 EMPLOYEE STOCK PURCHASE PLAN


The purpose of this Plan is to provide eligible employees of Open Solutions Inc.
(the "Company") and certain of its subsidiaries with opportunities to purchase
shares of the Company's common stock, $0.01 par value (the "Common Stock"). Two
million (2,000,000) shares of Common Stock in the aggregate have been approved
for this purpose. This Plan is intended to qualify as an "employee stock
purchase plan" as defined in Section 423 of the Internal Revenue Code of 1986,
as amended (the "Code"), and the regulations promulgated thereunder, and shall
be interpreted consistent therewith.

       1.    Administration. The Plan will be administered by the Company's
Board of Directors (the "Board") or by one or more committees or subcommittees
appointed by the Board (a "Committee"). The Board or a Committee has authority
to make rules and regulations for the administration of the Plan and its
interpretation and decisions with regard thereto shall be final and conclusive.

       2.    Eligibility. All employees of the Company, including Directors who
are employees, and all employees of any subsidiary of the Company (as defined in
Section 424(f) of the Code) designated by the Board or a Committee from time to
time (a "Designated Subsidiary"), are eligible to participate in any one or more
of the offerings of Options (as defined in Section 9) to purchase Common Stock
under the Plan provided that:

             (a)   they are customarily employed by the Company or a Designated
       Subsidiary for more than 20 hours a week and for more than five months in
       a calendar year; and

             (b)   they are employees of the Company or a Designated Subsidiary
       on the first day of the applicable Plan Period (as defined below).

       No employee may be granted an option hereunder if such employee,
immediately after the option is granted, owns 5% or more of the total combined
voting power or value of the stock of the Company or any subsidiary. For
purposes of the preceding sentence, the attribution rules of Section 424(d) of
the Code shall apply in determining the stock ownership of an employee, and all
stock which the employee has a contractual right to purchase shall be treated as
stock owned by the employee.

       3.    Offerings. The Company will make one or more offerings
("Offerings") to employees to purchase stock under this Plan. Offerings will
begin each December 1 and June 1, or the first business day thereafter (the
"Offering Commencement Dates"). Each Offering Commencement Date will begin a
six-month period (a "Plan Period") during which payroll deductions will be made
and held for the purchase of Common Stock at the end of the Plan Period. The
Board or a Committee may, at its discretion, choose a different Plan Period of
twelve (12) months or less for subsequent Offerings. Notwithstanding anything to
the contrary, the first Plan Period shall begin on January 1, 2004 and end on
May 31, 2004.


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       4.    Participation. An employee eligible on the Offering Commencement
Date of any Offering may participate in such Offering by completing and
forwarding a payroll deduction authorization form to the employee's appropriate
payroll office at least ten days prior to the applicable Offering Commencement
Date. The form will authorize a regular payroll deduction from the Compensation
received by the employee during the Plan Period. Unless an employee files a new
form or withdraws from the Plan, his deductions and purchases will continue at
the same rate for future Offerings under the Plan as long as the Plan remains in
effect. The term "Compensation" means the amount of money reportable on the
employee's Federal Income Tax Withholding Statement.

       5.    Deductions. The Company will maintain payroll deduction accounts
for all participating employees. With respect to any Offering made under this
Plan, an employee may authorize a payroll deduction in any dollar amount up to a
maximum of 10% of the Compensation he or she receives during the Plan Period or
such shorter period during which deductions from payroll are made. Payroll
deductions may be at the rate of 2%, 4%, 6%, 8% or 10% of Compensation with any
change in compensation during the Plan Period to result in an automatic
corresponding change in the dollar amount withheld.

       6.    Deduction Changes. An employee may increase, decrease or
discontinue his payroll deduction during any Plan Period by filing a new payroll
deduction authorization form. If an employee elects to discontinue his payroll
deductions during a Plan Period, but does not elect to withdraw his funds
pursuant to Section 8 hereof, funds deducted prior to his election to
discontinue will be applied to the purchase of Common Stock on the Exercise Date
(as defined below).

       7.    Interest. Interest will not be paid on any employee accounts,
except to the extent that the Board or a Committee, in its sole discretion,
elects to credit employee accounts with interest at such per annum rate as it
may from time to time determine.

       8.    Withdrawal of Funds. An employee may at any time prior to the close
of business on the last business day in a Plan Period and for any reason
permanently draw out the balance accumulated in the employee's account and
thereby withdraw from participation in an Offering. Partial withdrawals are not
permitted. The employee may not begin participation again during the remainder
of the Plan Period. The employee may participate in any subsequent Offering in
accordance with terms and conditions established by the Board or a Committee.

       9.    Purchase of Shares. On the Offering Commencement Date of each Plan
Period, the Company will grant to each eligible employee who is then a
participant in the Plan an option ("Option") to purchase on the last business
day of such Plan Period (the "Exercise Date"), at the Option Price hereinafter
provided for, the largest number of whole shares of Common Stock of the Company
as does not exceed the number of shares determined by multiplying $2,083 by the
number of full months in the Plan Period and dividing the result by the closing
price (as defined below) on the Offering Commencement Date of such Plan Period.

       Notwithstanding the above, no employee may be granted an Option (as
defined in Section 9) which permits his rights to purchase Common Stock under
this Plan and any other employee stock purchase plan (as defined in Section
423(b) of the Code) of the Company and its



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subsidiaries, to accrue at a rate which exceeds $25,000 of the fair market value
of such Common Stock (determined at the Offering Commencement Date of the Plan
Period) for each calendar year in which the Option is outstanding at any time.

       The purchase price for each share purchased will be 95% of the closing
price of the Common Stock on the Exercise Date. Such closing price shall be (a)
the closing price on any national securities exchange on which the Common Stock
is listed, (b) the closing price of the Common Stock on the Nasdaq National
Market or (c) the average of the closing bid and asked prices in the
over-the-counter-market, whichever is applicable, as published in The Wall
Street Journal. If no sales of Common Stock were made on such a day, the price
of the Common Stock for purposes of clauses (a) and (b) above shall be the
reported price for the next preceding day on which sales were made.

       Each employee who continues to be a participant in the Plan on the
Exercise Date shall be deemed to have exercised his Option at the Option Price
on such date and shall be deemed to have purchased from the Company the number
of full shares of Common Stock reserved for the purpose of the Plan that his
accumulated payroll deductions on such date will pay for, but not in excess of
the maximum number determined in the manner set forth above.

       Any balance remaining in an employee's payroll deduction account at the
end of a Plan Period will be automatically refunded to the employee, except that
any balance which is less than the purchase price of one share of Common Stock
will be carried forward into the employee's payroll deduction account for the
following Offering, unless the employee elects not to participate in the
following Offering under the Plan, in which case the balance in the employee's
account shall be refunded.

       10.   Issuance of Certificates. Certificates representing shares of
Common Stock purchased under the Plan may be issued only in the name of the
employee, in the name of the employee and another person of legal age as joint
tenants with rights of survivorship, or (in the Company's sole discretion) in
the name of a brokerage firm, bank or other nominee holder designated by the
employee. The Company may, in its sole discretion and in compliance with
applicable laws, authorize the use of book entry registration of shares in lieu
of issuing stock certificates.

       11.   Rights on Retirement, Death or Termination of Employment. In the
event of a participating employee's termination of employment prior to the last
business day of a Plan Period, no payroll deduction shall be taken from any pay
due and owing to an employee and the balance in the employee's account shall be
paid to the employee or, in the event of the employee's death, (a) to a
beneficiary previously designated in a revocable notice signed by the employee
(with any spousal consent required under state law) or (b) in the absence of
such a designated beneficiary, to the executor or administrator of the
employee's estate or (c) if no such executor or administrator has been appointed
to the knowledge of the Company, to such other person(s) as the Company may, in
its discretion, designate. If, prior to the last business day of the Plan
Period, the Designated Subsidiary by which an employee is employed shall cease
to be a subsidiary of the Company, or if the employee is transferred to a
subsidiary of the Company that is not a Designated Subsidiary, the employee
shall be deemed to have terminated employment for the purposes of this Plan.



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       12.   Optionees Not Stockholders. Neither the granting of an Option to an
employee nor the deductions from his pay shall constitute such employee a
stockholder of the shares of Common Stock covered by an Option under this Plan
until such shares have been purchased by and issued to him.

       13.   Rights Not Transferable. Rights under this Plan are not
transferable by a participating employee other than by will or the laws of
descent and distribution, and are exercisable during the employee's lifetime
only by the employee.

       14.   Application of Funds. All funds received or held by the Company
under this Plan may be combined with other corporate funds and may be used for
any corporate purpose.

       15.   Adjustment in Case of Changes Affecting Common Stock. In the event
of a subdivision of outstanding shares of Common Stock, or the payment of a
dividend in Common Stock, the number of shares approved for this Plan, and the
share limitation set forth in Section 9, shall be increased proportionately, and
such other adjustment shall be made as may be deemed equitable by the Board or a
Committee. In the event of any other change affecting the Common Stock, such
adjustment shall be made as may be deemed equitable by the Board or a Committee
to give proper effect to such event.

       16.   Merger. If the Company shall at any time merge or consolidate with
another corporation and the holders of the capital stock of the Company
immediately prior to such merger or consolidation continue to hold at least 80%
by voting power of the capital stock of the surviving corporation ("Continuity
of Control"), the holder of each Option then outstanding will thereafter be
entitled to receive at the next Exercise Date upon the exercise of such Option
for each share as to which such Option shall be exercised the securities or
property which a holder of one share of the Common Stock was entitled to upon
and at the time of such merger or consolidation, and the Board or a Committee
shall take such steps in connection with such merger or consolidation as the
Board or a Committee shall deem necessary to assure that the provisions of
Section 15 shall thereafter be applicable, as nearly as reasonably may be, in
relation to the said securities or property as to which such holder of such
Option might thereafter be entitled to receive thereunder.

       In the event of a merger or consolidation of the Company with or into
another corporation which does not involve Continuity of Control, or of a sale
of all or substantially all of the assets of the Company while unexercised
Options remain outstanding under the Plan, (a) subject to the provisions of
clauses (b) and (c), after the effective date of such transaction, each holder
of an outstanding Option shall be entitled, upon exercise of such Option, to
receive in lieu of shares of Common Stock, shares of such stock or other
securities as the holders of shares of Common Stock received pursuant to the
terms of such transaction; or (b) all outstanding Options may be cancelled by
the Board or a Committee as of a date prior to the effective date of any such
transaction and all payroll deductions shall be paid out to the participating
employees; or (c) all outstanding Options may be cancelled by the Board or a
Committee as of the effective date of any such transaction, provided that notice
of such cancellation shall be given to each holder of an Option, and each holder
of an Option shall have the right to exercise such Option in full based on
payroll deductions then credited to his account


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as of a date determined by the Board or a Committee, which date shall not be
less than ten (10) days preceding the effective date of such transaction.

       17.   Amendment of the Plan. The Board may at any time, and from time to
time, amend this Plan in any respect, except that (a) if the approval of any
such amendment by the stockholders of the Company is required by Section 423 of
the Code, such amendment shall not be effected without such approval, and (b) in
no event may any amendment be made which would cause the Plan to fail to comply
with Section 423 of the Code.

       18.   Insufficient Shares. In the event that the total number of shares
of Common Stock specified in elections to be purchased under any Offering plus
the number of shares purchased under previous Offerings under this Plan exceeds
the maximum number of shares issuable under this Plan, the Board or a Committee
will allot the shares then available on a pro rata basis.

       19.   Termination of the Plan. This Plan may be terminated at any time by
the Board. Upon termination of this Plan all amounts in the accounts of
participating employees shall be promptly refunded.

       20.   Governmental Regulations. The Company's obligation to sell and
deliver Common Stock under this Plan is subject to listing on a national stock
exchange or quotation on the Nasdaq National Market (to the extent the Common
Stock is then so listed or quoted) and the approval of all governmental
authorities required in connection with the authorization, issuance or sale of
such stock.

       21.   Governing Law. The Plan shall be governed by Delaware law except to
the extent that such law is preempted by federal law.

       22.   Issuance of Shares. Shares may be issued upon exercise of an Option
from authorized but unissued Common Stock, from shares held in the treasury of
the Company, or from any other proper source.

       23.   Notification upon Sale of Shares. Each employee agrees, by entering
the Plan, to promptly give the Company notice of any disposition of shares
purchased under the Plan where such disposition occurs within two years after
the date of grant of the Option pursuant to which such shares were purchased.

       24.   Withholding. Each employee shall, no later than the date of the
event creating the tax liability, make provision satisfactory to the Board for
payment of any taxes required by law to be withheld in connection with any
transaction related to Options granted to or shares acquired by such employee
pursuant to the Plan. The Company may, to the extent permitted by law, deduct
any such taxes from any payment of any kind otherwise due to an employee.



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       25.   Effective Date and Approval of Shareholders. The Plan shall take
effect upon the effectiveness of the Company's registration statement under the
Securities Act relating to the IPO, subject to approval by the stockholders of
the Company as required by Section 423 of the Code, which approval must occur
within twelve months of the adoption of the Plan by the Board.


                                            Adopted by the Board of Directors
                                            on August 27, 2003

                                            Approved by the stockholders on
                                            October 6, 2003

                                            First sentence of third paragraph of
                                            Section 9 amended by the Board of
                                            Directors on November 16, 2005



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