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                                                                   EXHIBIT 10.42
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                          REGISTRATION RIGHTS AGREEMENT

                                      AMONG

                                INTERLIANT, INC.,

                                     AND THE

                                    INVESTORS

                           Dated as of April 16, 2001
<PAGE>


                                TABLE OF CONTENTS

                                                                            Page

1.   Definitions. .............................................................1

2.   Required Registration. ...................................................2

3.   Incidental Registration. .................................................4

4.   Registration Procedures. .................................................6

5.   Expenses. ................................................................7

6.   Indemnification and Contribution. ........................................7

7.   Market Stand-Off Agreement. ..............................................9

8.   Miscellaneous. ...........................................................9

                                       i

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                          REGISTRATION RIGHTS AGREEMENT

     Registration Rights Agreement, dated as of April 16, 2001, among
INTERLIANT, INC., a Delaware corporation (the "Company") and the INVESTORS (as
hereinafter defined).

                                   WITNESSETH:
                                   ----------

     WHEREAS, the Company and the Investors have entered into a Securities
Purchase Agreement (the "Purchase Agreement"), dated of even date herewith,
                         ------------------
pursuant to which the Company may issue and sell to the Investors, and the
Investors may purchase from the Company, Convertible Notes (as such term is
defined in the Purchase Agreement) in the aggregate principal amount of
$19,000,000 and warrants (the "Warrants") to purchase shares of the Company's
                               --------
Common Stock, par value $.01 per share (the "Common Stock"); and
                                             ------------

     WHEREAS, in order to induce the Investors to enter into the Purchase
Agreement (and to purchase such Convertible Notes and Warrants) the Company has
agreed to provide certain registration rights with respect thereto;

     NOW, THEREFORE, in consideration of the foregoing, the mutual covenants and
agreements contained herein and for other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, it is agreed as
follows:

     1. Definitions. The following terms shall have (unless other wise provided
        -----------
elsewhere in this Registration Rights Agreement) the following respective
meanings (such meanings being equally applicable to both the singular and plural
form of the terms defined):

     "Agreement" means this Registration Rights Agreement, including all
amendments, modifications and supplements and any exhibits or schedules to any
of the foregoing, and shall refer to the Agreement as the same may be in effect
at the time such reference becomes operative.

     "Charter Investors" means Charterhouse Equity Partners III, L.P. and Chef
      -----------------
Nominees Limited.


     "Charter Registration Request" has the meaning given to it in Section 2(a).
      ----------------------------

     "Commission" means the United States Securities and Exchange Commission.
      ----------

     "Common Stock" has the meaning given to it in the recitals hereto.
      ------------

     "Convertible Notes" has the meaning given to it in the Purchase Agreement.
      ----------------

     "Demand Investor" has the meaning given in Section 3(c)(i).

     "Investors" means the Charter Investors and the Softbank Investors.

     "Maximum Offering Size" has the meaning given to it in Section 2(d).
<PAGE>
     "NASD" means the National Association of Securities Dealers, Inc., or any
successor corporation thereto.

     "Parity Piggyback Registration Securities" means those securities of the
Company that have "Piggyback Registration Rights" pursuant to the Registration
Rights Agreement dated as of January 27, 2000 among the Company and the other
parties thereto.

     "Purchase Agreement" has the meaning given to it in the recitals hereto.

     "Registering Security Holder" has the meaning given to it in Section 3.

     "Registrable Securities" means, collectively, (i) the shares of Common
Stock issuable upon conversion of the Convertible Notes, (ii) any shares of
Common Stock issuable upon exercise of Warrants, (iii) any shares of Common
Stock hereafter acquired by the Investors (excluding any shares of Common Stock
acquired by any Investor prior to the date hereof) or (iv) any shares of Common
Stock hereafter distributed to the Investors by the Company as a stock dividend,
stock split, recapitalization, reclassification or otherwise with respect to the
Convertible Notes, the Warrants or the shares of Common Stock covered by clauses
(i) (ii) or (iii) above; provided, however, that any such securities shall cease
to be Registrable Securities when (i) such securities shall have been registered
under the Securities Act, the registration statement with respect to the sale of
such securities shall have become effective under the Securities Act and such
securities shall have been disposed of pursuant to such effective registration
statement, (ii) such securities shall have been otherwise transferred, if new
certificates or other evidences of ownership for them not bearing a legend
restricting further transfer and not subject to any stop transfer order or other
restrictions on transfer shall have been delivered by the Company and subsequent
disposition of such securities shall not require registration or qualification
of such securities under the Securities Act or any state securities law then in
force, (iii) such securities shall cease to be outstanding or (iv) such
securities shall be eligible for sale pursuant to Rule 144(k) under the
Securities Act or any successor rule which permits resale of such securities
without restriction.

     "Securities Act" has the meaning given to it in Section 2(a).

     "Softbank Investors" means the entities set forth on the signature page
hereto under the caption "Softbank Investors".

     "Softbank Registration Request" has the meaning given to it in Section
2(a).

     "Warrants" has the meaning given to it in the recitals hereto.

     2. Required Registration. (a) Upon receipt of a written request (x) from
        ---------------------
the Charter Investors (a "Charter Registration Request") or (y) from the
Softbank Investors (a "Softbank Registration Request" and, collectively with a
Charter Registration Request, a "Registration Request"), requesting that the
Company effect the registration of Registrable Securities under the Securities
Act of 1933, as amended (the "Securities Act"), the Company shall, as
expeditiously as is possible, use its best efforts to effect the registration
under the Securities Act of all shares of Registrable Securities which the
Company has been so requested to register by the Charter Investors or the
Softbank Investors, as applicable; provided, however,

                                       2
<PAGE>

that, subject to the provisions of the immediately following sentence, the
Company shall not be required to effect more than four registrations of
Registrable Securities on Form S-1 or Form S-2 pursuant to this Section 2 for
the Charter Investors or more than four registrations of Registrable Securities
on Form S-1 or Form S-2 pursuant to this Section 2 for the Softbank Investors.
The Company shall be obligated to file an unlimited number of registration
statements on Form S-3 (or any successor form) pursuant to any request therefor
received from a Charter Investor or a Softbank Investor. In order to count as an
"effected" registration statement, such registration statement shall not have
been withdrawn and all Registrable Securities registered pursuant to it
(excluding any overallotment shares) shall have been sold. The Company shall
have the right to defer the filing of any registration statement requested
pursuant to this Section 2 for a period not to exceed ninety (90) days if in the
good faith determination of the Board of Directors of the Company the filing of
such registration statement would be seriously detrimental to the Company.

     (b) If the Charter Investors or the Softbank Investors, as applicable,
shall have delivered a Registration Request to the Company, the Company shall
give written notice thereof to the Charter Investors (in the case of a Softbank
Registration Request) and the Softbank Investors (in the case of a Charter
Registration Request) at least 20 days before the initial filing with the
Commission of the Registration Statement relating thereto, which notice shall
set forth the intended method of disposition of the securities proposed to be
registered by the Company. The notice shall offer to include in such filing the
aggregate number of shares of Registrable Securities as the Charter Investors
(in the case of a Softbank Registration Request) or the Softbank Investors (in
the case of a Charter Registration Request) may request. If the Charter
Investors (in the case of a Softbank Registration Request) or the Softbank
Investors (in the case of a Charter Registration Request) shall desire to have
Registrable Securities registered under this Section 2(b), they shall advise the
Company in writing within 10 days after the date of receipt of such offer from
the Company, setting forth the amount of such Registrable Securities for which
registration is requested. The Company shall thereupon include in such filing
the number of shares of Registrable Securities for which registration is so
requested, subject to Section 2(d)(i), and shall use its best efforts to effect
registration under the Securities Act of such shares.

     (c) Underwriters. The managing underwriter or underwriters of any public
offering effected pursuant to this Section 2 shall be reasonably acceptable to
the Charter Investors (in the case of a Charter Registration Request) or the
Softbank Investors (in the case of a Softbank Registration Request) and the
Company.

     (d) Priority in Requested Registration. If the managing underwriter of a
registration pursuant to this Section 2 shall advise the Company in writing
that, in its view, the number or proposed mix of securities requested to be
included in such registration (including securities which the Company requests
to be included ) exceeds the largest number of securities which can be sold
without having a material adverse effect on such offering (the "Maximum Offering
Size"), including the price at which such securities can be sold, the Company
will include in such registration:

          (i) first, the Registrable Securities requested to be included in such
     registration by the Charter Investors or by the Softbank Investors, as

                                       3
<PAGE>

     applicable, pursuant to Section 2(a), and the Registrable Securities
     requested to be included in such registration by the Charter Investors (in
     the case of a Softbank Registration Request) or the Softbank Investors (in
     the case of a Charter Registration Request) pursuant to Section 2(b),
     allocated (if necessary) pro rata among the Charter Investors and the
     Softbank Investors on the basis of the relative number of Registrable
     Securities each of the Charter Investors and the Softbank Investors, as
     applicable, has requested to be included in such registration;

          (ii) second, securities of the Company to be sold for the account of
     the Company; and

          (iii) third, securities of the Company to be sold for the account of
     other persons, with such priorities among them as the Company shall
     determine.

     3. Incidental Registration.
        -----------------------

     (a) If the Company at any time proposes to file on its behalf and/or on
behalf of any of its security holders (the "Registering Security Holders") a
Registration Statement under the Securities Act on any form (other than a
Registration Statement on Form S-4 or S-8 or any successor form for securities
to be offered in a transaction of the type referred to in Rule 145 under the
Securities Act or to employees of the Company pursuant to any employee benefit
plan, respectively) for the registration of shares of Common Stock of the
Company, it will give written notice to all holders of Registrable Securities at
least 30 days before the initial filing with the Commission of such Registration
Statement, which notice shall set forth the intended method of disposition of
the securities proposed to be registered by the Company. The notice shall offer
to include in such filing the aggregate number of shares of Registrable
Securities as such holders may request.

     (b) Each holder of any such Registrable Securities desiring to have
Registrable Securities registered under this Section 3 shall advise the Company
in writing within 20 days after the date of receipt of such offer from the
Company, setting forth the amount of such Registrable Securities for which
registration is requested. The Company shall thereupon include in such filing
the number of shares of Registrable Securities for which registration is so
requested, subject to Section 3(c), and shall use its best efforts to effect
registration under the Securities Act of such shares.

     (c) Priority In Incidental Registrations. If the managing underwriter of a
registration pursuant to this Section 3 shall advise the Company in writing
that, in its view, the number or mix of securities (including all Registrable
Securities) which the Company, the Charter Investors, the Softbank Investors and
any other persons intend to include in such registration exceeds the Maximum
Offering Size:

          (i) If such registration was initiated by the Company, and not by any
     other shareholder holding demand registration rights (a "Demand

                                       4
<PAGE>

Investor"), then the Company will include in such registration, in the priority
listed below, securities up to the Maximum Offering Size:

          (A) first, securities of the Company to be sold for the account of the
     Company;

          (B) second, (x) the Registrable Securities requested to be included in
     such registration pursuant to Section 3 hereof by any Charter Investor or
     Softbank Investor holding such Registrable Securities and (y) the
     securities requested to be included in such registration by any holder of
     Parity Piggyback Registration Securities and by any Demand Investor,
     allocated (if necessary) pro rata among such Charter Investors, Softbank
     Investors, holders of Parity Piggyback Registration Securities and Demand
     Investors on the basis of the relative number of (I) Registrable Securities
     held by the Charter Investors and the Softbank Investors, and (II) Parity
     Piggyback Registration Securities held by the holders of Parity Piggyback
     Registration Securities; and

          (C) third, securities of the Company to be sold for the account of
     other persons, with such priorities among them as the Company shall
     determine.

     or

          (ii) If such registration was initiated by a Demand Investor, then the
     Company will include in such registration, in the priority listed below,
     securities up to the Maximum Offering Size:

          (A) first, the securities requested to be registered by such Demand
     Investor;

          (B) second, the Registrable Securities requested to be included in
     such registration by the Charter Investors, the Softbank Investors and the
     holders of Parity Piggyback Registration Securities pursuant to Section 3
     hereof, allocated (if necessary) pro rata among all of such Charter
     Investors, Softbank Investors and holders of Parity Piggyback Registration
     Securities on the basis of the relative number of securities of the Company
     held by each such Charter Investor, Softbank Investor or holder of
     Piggyback Registration Securities;

          (C) third, securities of the Company to be sold for the account of the
     Company; and

          (D) fourth, securities of the Company to be sold for the account of
     other persons, with such priorities among them as the Company shall
     determine.

                                       5
<PAGE>

     4. Registration Procedures. If the Company is required by the provisions of
        -----------------------
Section 2 or 3 to use its best efforts to effect the registration of any of its
securities under the Securities Act, the Company will, as expeditiously as
possible:

     (a) prepare and file with the Commission a Registration Statement with
respect to such securities and use its best efforts to cause such Registration
Statement to become and remain effective for a period of time required for the
disposition of such securities by the holders thereof, but not to exceed 180
days;

     (b) prepare and file with the Commission such amendments and supplements to
such Registration Statement and the prospectus used in connection therewith as
may be necessary to keep such Registration Statement effective and to comply
with the provisions of the Securities Act with respect to the sale or other
disposition of all securities covered by such Registration Statement until the
earlier of such time as all of such securities have been disposed of in a public
offering or the expiration of 180 days;

     (c) furnish to the Investors such number of copies of a summary prospectus
or other prospectus, including a preliminary prospectus, in conformity with the
requirements of the Securities Act, and such other documents, as such selling
security holders may reasonably request;

     (d) use its best efforts to register or qualify the securities covered by
such Registration Statement under such other securities or blue sky laws of such
jurisdictions within the United States and Puerto Rico as each holder of such
securities shall request (provided, however, that the Company shall not be
obligated to qualify as a foreign corporation to do business under the laws of
any jurisdiction in which it is not then qualified or to file any general
consent to service of process), and do such other reasonable acts and things as
may be required of it to enable such holder to consummate the disposition in
such jurisdiction of the securities covered by such Registration Statement;

     (e) furnish, in connection with any registration of Registrable Securities,
on the date that such shares of Registrable Securities are delivered to the
underwriters for sale pursuant to such registration or, if such Registrable
Securities are not being sold through underwriters, on the date that the
Registration Statement with respect to such shares of Registrable Securities
becomes effective, (1) an opinion, dated such date, of the counsel representing
the Company for the purposes of such registration, addressed to the
underwriters, if any, and if such Registrable Securities are not being sold
through underwriters, then to the Investors, in customary form and covering
matters of the type customarily covered in such legal opinions; and (2) a
comfort letter dated such date, from the independent certified public
accountants of the Company, addressed to the underwriters, if any, and if such
Registrable Securities are not being sold through underwriters, then to the
Investors and, if such accountants refuse to deliver such letter to the
Investors, then to the Company in a customary form and covering matters of the
type customarily covered by such comfort letters and as the underwriters or such
holder(s) shall reasonably request;

     (f) enter into customary agreements (including an underwriting agreement in
customary form with customary indemnification provisions) and take such other

                                       6
<PAGE>

actions as are reasonably required in order to expedite or facilitate the
disposition of such Registrable Securities; and

     (g) otherwise use its best efforts to comply with all applicable rules and
regulations of the Commission, and make available to its security holders, as
soon as reasonably practicable, but not later than 18 months after the effective
date of the Registration Statement, an earnings statement covering the period of
at least 12 months beginning with the first full month after the effective date
of such Registration Statement, which earnings statements shall satisfy the
provisions of Section 11(a) of the Securities Act.

     It shall be a condition precedent to the obligation of the Company to take
any action pursuant to this Agreement in respect of the securities which are to
be registered at the request of the Investors that (i) the Investors shall
furnish to the Company such information regarding the securities held by the
Investors and the intended method of disposition thereof as the Company shall
reasonably request and as shall be required under the Securities Act in
connection with the action taken by the Company and (ii) that the Investors
shall deliver and perform under such underwriting agreement as may be reasonably
requested by the underwriters.

     5. Expenses. All expenses incurred in complying with this Agreement,
        --------
including, without limitation, all registration and filing fees (including all
expenses incident to filing with the NASD), printing expenses, fees and
disbursements of counsel for the Company and counsel for the Investors, expenses
of any special audits incident to or required by any such registration and
expenses of complying with the securities or blue sky laws of any jurisdictions
pursuant to Section 4(d), shall be paid by the Company, except that the Company
shall not be liable for any fees, discounts or commissions to any underwriter in
respect of the securities sold by the Investors.

     6. Indemnification and Contribution. (a) In the event of any registration
        --------------------------------
of any Registrable Securities under the Securities Act pursuant to this
Agreement, the Company shall indemnify and hold harmless each Investor, its
directors and officers, and each other Person (including each underwriter) who
participated in the offering of such Registrable Securities and each other
Person, if any, who controls the Investor or such participating Person within
the meaning of the Securities Act, against any losses, claims, damages or
liabilities, joint or several, the Investor or any such director or officer or
participating Person or controlling Person may become subject under the
Securities Act, the Securities Exchange Act, state securities or blue sky laws
or any other statute or at common law, insofar as such losses, claims, damages
or liabilities (or actions in respect thereof) arise out of or are based upon
(i) any untrue or alleged untrue statement of any material fact contained in any
Registration Statement under which such securities were registered under the
Securities Act, any preliminary prospectus or final prospectus contained
therein, or any amendment or supplement thereto, (ii) any omission or alleged
omission to state therein a material fact required to be stated therein or
necessary to make the statements therein not misleading or (iii) any violation
or alleged violation by the Company of the Securities Act, the Securities
Exchange Act, state securities or blue sky laws, any other statute or common
law; and the Company shall reimburse the Investor or such director, officer or
participating Person or controlling Person for any legal or any other expenses
reasonably incurred by the Investor or such director, officer or participating
Person or controlling Person in connection with investigating or defending any
such loss, claim, damage, liability or action;

                                       7
<PAGE>

provided, however, that the Company shall not be liable in any such case to the
extent that any such loss, claim, damage or liability arises out of or is based
upon any untrue statement or omission made in such Registration Statement,
preliminary prospectus, prospectus or amendment or supplement in reliance upon
and in conformity with written information furnished to the Company by the
Investor specifically for use therein. Such indemnity shall remain in full force
and effect regardless of any investigation made by or on behalf of the Investor
or such director, officer or participating Person or controlling Person, and
shall survive the transfer of such securities by the Investor.

     (b) In the event of any registration of any Registrable Securities under
the Securities Act pursuant to this Agreement, each Investor shall indemnify and
hold harmless the Company, its directors and officers, and each other Person
(including each underwriter) who participated in the offering of such
Registrable Securities and each other Person, if any, who controls the Company
or such participating Person within the meaning of the Securities Act, against
any losses, claims, dam ages or liabilities, joint or several, to which the
Company or any such director or officer or participating Person or controlling
Person may become subject under the Securities Act, the Securities Exchange Act,
state securities or blue sky laws or any other statute or at common law, insofar
as such losses, claims, damages or liabilities (or actions in respect thereof)
arise out of or are based upon any untrue or alleged untrue statement of any
material fact contained in any Registration Statement under which such
securities were registered under the Securities Act, any preliminary prospectus
or final prospectus contained therein, or any amendment or supplement thereto,
or arise out of or are based upon any omission or alleged omission to state
therein a material fact required to be stated therein or necessary to make the
statements therein not misleading, in each case where such statement or omission
is in conformity with written information provided by the Investor expressly for
use therein, and shall reimburse the Company or such director, officer or
participating Person or controlling Person for any legal or any other expenses
reasonably incurred by the Company or such director, officer or participating
Person or controlling Person in connection with investigating or defending any
such loss, claim, damage, liability or action; provided, however, that the
Investor shall not be liable for any amounts in excess of the net proceeds
received by it for the sale of its shares. Such indemnity shall remain in full
force and effect regardless of any investigation made by or on behalf of the
Company or such director, officer or participating Person or controlling Person,
and shall survive the transfer of such securities by the Investor.

     (c) Each party entitled to indemnification under this Section 6 shall give
notice to the party required to provide indemnification promptly after such
indemnified party has actual knowledge of any claim as to which indemnity may be
sought, and shall permit the indemnifying party to assume the defense of any
such claim or any litigation resulting therefrom; provided, that counsel for the
indemnifying party, who shall conduct the defense of such claim or litigation,
shall be approved by the indemnified party (whose approval shall not be
unreasonably withheld); and, provided, further, that the failure of any
indemnified party to give notice as provided herein shall not relieve the
indemnifying party of its obligations under this Section 6. The indemnified
party may participate in such defense at such party's expense; provided,
however, that the indemnifying party shall pay such expense if representation of
such indemnified party by the counsel retained by the indemnifying party would
be inappropriate due to actual or potential differing interests between the
indemnified party and any other party represented by such counsel in such
proceeding. No indemnifying party, in the defense of any

                                       8
<PAGE>

such claim or litigation shall, except with the consent of each indemnified
party, consent to entry of any judgment or enter into any settlement which does
not include as an unconditional term thereof the giving by the claimant or
plaintiff to such indemnified party of a release from all liability in respect
of such claim or litigation, and no indemnified party shall consent to entry of
any judgment or settle such claim or litigation without the prior written
consent of the indemnifying party.

     (d) If the indemnification provided for in this Section 6 is unavailable to
an indemnified party hereunder in respect of any losses, claims, damages,
liabilities or expenses referred to therein, then the indemnifying party, in
lieu of indemnifying such indemnified party, shall contribute to the amount paid
or payable by such indemnified party as a result of such losses, claims,
damages, liabilities or expenses in such proportion as is appropriate to reflect
the relative fault of the indemnifying party and indemnified parties in
connection with the actions which resulted in such losses, claims, damages,
liabilities or expenses, as well as any other relevant equitable considerations;
provided that in the case of the Investor, such contribution shall not exceed
any amounts in excess of the net proceeds received by the Investor for the sale
of its shares. The relative fault of such indemnifying party and indemnified
parties shall be determined by reference to, among other things, whether any
action in question, including any untrue or alleged untrue statement of a
material fact or omission or alleged omission to state a material fact, has
been made by, or relates to information supplied by, such indemnifying party or
indemnified parties, and the parties' relative intent, knowledge, access to
information and opportunity to correct or prevent such action. The amount paid
or payable by a party as a result of the losses, claims, damages, liabilities
and expenses referred to above shall be deemed to include any legal or other
fees or expenses reason ably incurred by such party in connection with any
investigation or proceeding.

     The parties hereto agree that it would not be just and equitable if
contribution pursuant to this Section 6(d) were determined by pro rata
allocation or by any other method of allocation which does not take account of
the equitable considerations referred to in the immediately preceding paragraph.
No Person guilty of fraudulent misrepresentation (within the meaning of Section
11(f) of the Securities Act) shall be entitled to contribution from any Person
who was not also guilty of such fraudulent misrepresentation.

     (e) The obligations of the Company and the Investors under this Section 6
shall survive the completion of any offering of Registrable Shares in a
registration statement under Sections 2 and 3, and otherwise.

     7. Market Stand-Off Agreement. If requested by an underwriter of securities
        --------------------------
of the Company the Investors shall not sell or otherwise transfer or dispose of
any securities held by them during the one hundred twenty (120) day period
following the effective date of a Registration Statement; provided, that all
officers and directors of the Company, as well as all beneficial owners of
greater than 10% of the Company's Common Stock, enter into similar agreements.

     8. Miscellaneous.
        -------------

                                       9
<PAGE>

     (a) Remedies. The Investors, in addition to being entitled to exercise all
rights granted by law, including recovery of damages, will be entitled to
specific performance of their rights under this Agreement. The Company agrees
that monetary damages would not be adequate compensation for any loss incurred
by reason of a breach by it of the provisions of this Agreement and hereby
agrees to waive the defense in any action for specific performance that a remedy
at law would be adequate.

     (b) Amendments and Waivers. Except as otherwise provided herein, the
provisions of this Agreement may not be amended, modified or supplemented, and
waivers or consents to departure from the provisions hereof may not be given
unless the Company and the Investors have approved the same in writing.

     (c) Notices. Any notice, demand, request, con sent, approval, declaration,
delivery or other communication hereunder to be made pursuant to the provisions
of this Agreement shall be sufficiently given or made if in writing and (i)
delivered in person with receipt acknowledged, (ii) sent by registered or
certified mail, return receipt requested, postage prepaid, (iii) sent by
overnight courier with guaranteed next-day delivery, or (iv) sent by telex or
telecopier, in each case addressed as follows:

          (i) If to the Charter Investors, to them at:

                    c/o Charterhouse Group International, Inc.
                    535 Madison Avenue
                    New York, New York 10022-4299
                    Attention: Thomas C. Dircks
                    Fax: (212) 750-9704

          (ii) If to the Softbank Investors, to them at:

                    c/o Softbank Venture Capital
                    200 West Evelyn Avenue, Suite 200
                    Mountain View, California 94043
                    Attention: General Counsel

          (iii) If to the Company, to it at:

                    Interliant, Inc.
                    Two Manhattanville Road
                    Purchase, New York 10577
                    Attention: General Counsel

or at such other address as may be substituted by notice given as
hereinprovided. The giving of any notice required hereunder may be waived in
writing by the party entitled to receive such notice. Every notice, demand,
request, consent, approval, declaration, delivery or other communication
hereunder shall be deemed to have been duly given or served on the date on which
personally delivered, with receipt acknowledged, or three (3) Business Days
after the

                                       10
<PAGE>

same shall have been deposited in the United States mail, one business day after
sent by overnight courier or on the day telexed or telecopied.

     (d) Successors and Assigns. This Agreement shall inure to the benefit of
and be binding upon (i) the successors of each of the parties hereto and (ii)
the assigns of each of the Investors, including any Person to whom Registrable
Securities are transferred if the transferee or assignee acquires at least
twenty- five percent (25%) of the then outstanding Registrable Securities held
by such Investor or if the transferee or assignee of Registrable Securities is a
member, general partner, limited partner, retired partner or other affiliate of
any Investor; provided that any such transferee or assignee shall execute a
counterpart of, or shall otherwise become bound in writing by the requirements
of, this Agreement and be considered an "Investor" for purposes of this
Agreement.

     (e) Mergers, Etc. The Company shall not, directly or indirectly, enter into
any merger, consolidation or reorganization in which the Company shall not be
the surviving corporation unless the proposed surviving corporation shall, prior
to such merger, consolidation or reorganization, agree in writing to assume the
obligations of the Company under this Agreement, and for that purpose references
hereunder to "Registrable Securities" shall be deemed to be references to the
securities which holders of then Registrable Securities would be entitled to
receive in exchange for Registrable Securities under any such merger,
consolidation or reorganization; provided, however, that the provisions of this
Section 8(f) shall not apply in the event of any merger, consolidation or
reorganization in which the Company is not the surviving corporation if all
holders of then Registrable Shares are entitled to receive in exchange for such
Registrable Securities consideration consisting solely of (i) cash, (ii)
securities of the acquiring corporation which may be immediately sold to the
public without registration under the Securities Act, or (iii) securities of the
acquiring corporation which the acquiring corporation has agreed to register
within 90 days of completion of the transaction for resale to the public
pursuant to the Securities Act.

     (f) Headings. The headings in this Agreement are for convenience of
reference only and shall not limit or other wise affect the meaning hereof.

     (g) Governing Law. This Agreement shall be governed by and construed in
accordance with the internal laws of the State of New York (i.e., without regard
to its conflicts of law rules).

     (h) Severability. Wherever possible, each pro vision of this Agreement
shall be interpreted in such manner as to be effective and valid under
applicable law, but if any pro vision of this Agreement shall be prohibited by
or invalid under applicable law, such provision shall be ineffective to the
extent of such prohibition or invalidity, without invalidating the remainder of
such provision or the remaining provisions of this Agreement.

                                  [END OF TEXT]

                                       11
<PAGE>

     IN WITNESS WHEREOF, the Company and the Purchaser have executed this
Registration Rights Agreement as of the day and year first above written.

                                       INTERLIANT, INC.


                                       By: /s/ William A. Wilson
                                              --------------------------
                                          Name: William A. Wilson
                                          Title: CFO


                                       CHARTERHOUSE EQUITY PARTNERS III, L.P.


                                       By:  CHUSA EQUITY INVESTORS III, L.P.,
                                             General Partner

                                            By:  CHARTERHOUSE EQUITY III, L.P.,
                                                  General Partner

                                                 By: /s/ Jay M. Gates
                                                    --------------------
                                                    Name: Jay M. Gates
                                                    Title: SVP

                                       CHEF NOMINEES LIMITED

                                       By:  CHARTERHOUSE GROUP
                                             INTERNATIONAL, INC.,
                                                  Attorney-in-Fact

                                       By: /s/ Jay M. Gates
                                          --------------------------------------
                                          Name:  Jay M. Gates
                                          Title: SVP

                                       12
<PAGE>

Softbank Investors:                    SOFTBANK TECHNOLOGY VENTURES VI L.P.

                                       By:  SBTV VI LLC, General Partner

                                               By: /s/ Bradley A. Feld
                                                  ---------------------------
                                                 Name:
                                                 Title:


                                       SOFTBANK U.S. VENTURES VI L.P.

                                       By:  SBTV VI LLC, General Partner

                                               By: /s/ Bradley A. Feld
                                                  ---------------------------
                                                 Name:
                                                 Title:


                                       SOFTBANK TECHNOLOGY VENTURES
                                                ADVISORS FUND VI L.P.

                                       By:  SBTV VI LLC, General Partner

                                               By: /s/ Bradley A. Feld
                                                  ---------------------------
                                                 Name:
                                                 Title:


                                       SOFTBANK TECHNOLOGY VENTURES
                                                SIDE FUND VI L.P.

                                       By:  SBTV VI LLC, General Partner

                                               By: /s/ Bradley A. Feld
                                                  ---------------------------
                                                 Name:
                                                 Title:

                                       13