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                                                                   Exhibit 10.26

                   SEPARATION AGREEMENT AND GENERAL RELEASE

                                 July 18, 2000

Mr. Robert Eisenberg
289 Kings Highway
Kennebunkport, ME


Dear Bob:

     In connection with the end of your employment with NaviSite, Inc. (the
"Company") on July 14, 2000, you are eligible to receive the separation
benefits described in the "Description of Separation Benefits" attached to this
letter as Attachment A if you sign and return this letter in the enclosed
envelope by August 10, 2000.  By signing and returning this letter, you will be
agreeing to the terms and conditions set forth in the numbered paragraphs below,
including the release of claims set forth in paragraph 3.  Therefore, you are
advised to consult with your attorney before signing this letter and you may
take up to twenty-one (21) days to do so.  If you sign this letter, you may
change your mind and revoke your agreement during the seven (7) day period after
you have signed it.  If you do not so revoke, this letter will become a binding
agreement between you and the Company upon the expiration of the seven (7) day
revocation period.

     If you choose not to sign this letter by August 10, 2000, you shall not
receive any separation benefits from the Company.  You will, however, receive
payment for any unused vacation time accrued through your last day of work.
Also, regardless of signing this letter, you may elect to continue receiving
group medical insurance pursuant to the federal "COBRA" law, 29 U.S.C. (S) 1161
et seq.  All premium costs shall be paid by you on a monthly basis for as long
as, and to the extent that, you remain eligible for COBRA continuation.  You
should consult the COBRA materials to be provided by the Company for details
regarding these benefits.  All other benefits, including life insurance and
long-term disability, ceased on your last day of employment.

     The following numbered paragraphs set forth the terms and conditions which
will apply if you timely sign and return this letter agreement and do not revoke
it within the seven (7) day period:

1.  SEPARATION DATE - Your effective date of separation from the Company is July
    14, 2000 (the "Separation Date").

2.  DESCRIPTION OF SEPARATION BENEFITS - The separation benefits paid to you if
    you timely sign and return this letter are described in the "Description of
    Separation Benefits" attached as Attachment A (the "separation benefits").

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3.  RELEASE - In consideration of the payment of the separation benefits, which
    you acknowledge you would not otherwise be entitled to receive, you hereby
    fully, forever, irrevocably and unconditionally release, remise and
    discharge the Company, its officers, directors, stockholders, corporate
    affiliates, subsidiaries, and parent companies (including CMGI, Inc.),
    agents and employees from any and all claims, charges, complaints, demands,
    actions, causes of action, suits, rights, debts, sums of money, costs,
    accounts, reckonings, covenants, contracts, agreements, promises, doings,
    omissions, damages, executions, obligations, liabilities, and expenses
    (including attorneys' fees and costs), of every kind and nature which you
    ever had or now have against the Company, its officers, directors,
    stockholders, corporate affiliates, subsidiaries and parent companies
    (including CMGI, Inc.), agents and employees arising out of your employment
    with or separation from the Company including, but not limited to, all
    employment discrimination claims under Title VII of the Civil Rights Act of
    1964, 42 U.S.C. (S)2000e et seq., the Age Discrimination in Employment Act,
    29 U.S.C., (S)621 et seq., the Americans With Disabilities Act of 1990, 42
    U.S.C., (S)12101 et seq., the Rehabilitation Act of 1973, 29 U.S.C. (S)701
    et seq.,and the Massachusetts Fair Employment Practices Act, M.G.L. c.151B,
    (S)1 et seq., all as amended, and all claims arising out of the Fair Credit
    Reporting Act, 15 U.S.C. (S)1681 et seq., the Employee Retirement Income
    Security Act of 1974 ("ERISA"), 29 U.S.C. (S)1001 et seq., the Massachusetts
    Civil Rights Act, M.G.L. c.12 (S)(S)11H and 11I, the Massachusetts Equal
    Rights Act, M.G.L. c.93 (S)102 and M.G.L. c.214, (S)1C, the Massachusetts
    Labor and Industries Act, M.G.L. c. 149, (S)1 et seq., and the Massachusetts
    Privacy Act, M.G.L. c.214, (S)1B, all as amended, and all common law claims
    including, but not limited to, actions in tort, defamation and breach of
    contract, and any claim or damage arising out of any relationship with the
    Company, employment with the Company or separation from the Company
    (including a claim for retaliation) under any common law theory or any
    federal, state or local ordinance not expressly referenced above.

4.  NON-DISCLOSURE AND NON-COMPETITION - You acknowledge your obligation to keep
    confidential all non-public information concerning the Company which you
    acquired during the course of your employment with the Company, as stated
    more fully in the non-disclosure agreement you executed at the inception of
    your employment which remains in full force and effect. You further
    acknowledge and reaffirm your obligations under any non-competition
    agreement that you may have previously executed for the benefit of the
    Company. That agreement/ those agreements shall remain in full force and
    effect to the extent permitted by law.

5.  RETURN OF COMPANY PROPERTY - You agree to return within seven (7) days of
    the execution of this letter agreement all Company property including, but
    not limited to, keys, files, records (and copies thereof), computer hardware
    and software, cellular phones, pagers, and Company vehicle, which is in your
    possession or control. You further agree to leave intact all electronic
    Company documents, including those which you developed or help develop
    during his employment.

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6.  NON-DISPARAGEMENT - You understand and agree that as a condition for payment
    to you of the consideration herein described, you shall not make any false,
    disparaging or derogatory statements to any media outlet, industry group,
    financial institution or current or former employee, consultant, client or
    customer of the Company regarding the Company or any of its directors,
    officers, employees, agents or representatives or about the Company's
    business affairs and financial condition.

7.  AMENDMENT - This letter agreement shall be binding upon the parties and may
    not be modified in any manner, except by an instrument in writing of
    concurrent or subsequent date signed by duly authorized representatives of
    the parties hereto. This letter agreement is binding upon and shall inure to
    the benefit of the parties and their respective agents, assigns, heirs,
    executors, successors and administrators.

8.  WAIVER OF RIGHTS - No delay or omission by the Company in exercising any
    right under this letter agreement shall operate as a waiver of that or any
    other right. A waiver or consent given by the Company on any one occasion
    shall be effective only in that instance and shall not be construed as a bar
    or waiver of any right on any other occasion.

9.  VALIDITY - Should any provision of this letter agreement be declared or be
    determined by any court of competent jurisdiction to be illegal or invalid,
    the validity of the remaining parts, terms or provisions shall not be
    affected thereby and said illegal or invalid part, term or provision shall
    be deemed not to be a part of this letter agreement.

10. CONFIDENTIALITY - You understand and agree that as a condition for payment
    to you of the consideration herein described, the terms and contents of this
    letter agreement, and the contents of the negotiations and discussions
    resulting in this letter agreement, shall be maintained as confidential by
    you and your agents and representatives and shall not be disclosed to any
    third party except to the extent required by federal or state law or as
    otherwise agreed to in writing by the Company.

11. NATURE OF AGREEMENT - You and the Company understand and agree that this
    letter agreement is a separation agreement and does not constitute an
    admission of liability or wrongdoing on the part of you, the Company, or any
    other person.

12. ACKNOWLEDGMENTS - You acknowledge that you have been given at least twenty-
    one (21) days to consider this letter agreement, including Attachment A, and
    that the Company advised you to consult with an attorney of your own
    choosing prior to signing this letter agreement. You understand that you may
    revoke this letter agreement for a period of seven (7) days after you sign
    this letter agreement, and the letter agreement shall not be effective or
    enforceable until the expiration of this seven (7) day revocation period.

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13. VOLUNTARY ASSENT - You affirm that no other promises or agreements of any
    kind have been made to or with you by any person or entity whatsoever to
    cause you to sign this letter agreement, and that you fully understand the
    meaning and intent of this letter agreement. You state and represent that
    you have had an opportunity to fully discuss and review the terms of this
    letter agreement, including Attachment A, with an attorney. You further
    state and represent that you have carefully read this letter agreement,
    including Attachment A, understand the contents herein, freely and
    voluntarily assent to all of the terms and conditions hereof, and sign your
    name of your own free act.

14. APPLICABLE LAW - This agreement shall be interpreted and construed by the
    laws of the Commonwealth of Massachusetts, without regard to conflict of
    laws provisions. You hereby irrevocably submit to and acknowledge and
    recognize the jurisdiction of the courts of the Commonwealth of
    Massachusetts, or if appropriate, a federal court located in Massachusetts
    (which courts, for purposes of this agreement, are the only courts of
    competent jurisdiction), over any suit, action or other proceeding arising
    out of, under or in connection with this letter agreement or the subject
    matter hereof.

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15. ENTIRE AGREEMENT - This letter agreement, including Attachment A, contains
    and constitutes the entire understanding and agreement between the parties
    hereto with respect to your separation benefits and the settlement of claims
    against the Company and cancels all previous oral and written negotiations,
    agreements, commitments, writings in connection therewith. Nothing in this
    paragraph, however, shall modify, cancel or supercede your obligations set
    forth in paragraph 4.


     If you have any questions about the matters covered in this letter, please
call Jeanne Knight at 978-946-7751 Human Resources department.

                              Very truly yours,

                               /s/ Scott N. Semel
                              --------------------------------
                              Name: Scott N. Semel
                              Title: General Counsel

     I hereby agree to the terms and conditions set forth above and in
Attachment A.  I have been given at least twenty-one (21) days to consider this
letter agreement (including Attachment A) and I have chosen to execute this on
the date below.  I intend that this letter agreement will become a binding
agreement between me and the Company if I do not revoke my acceptance in seven
(7) days.

/s/ Robert Eisenberg                          Date: July 26, 2000
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Robert Eisenberg


To be returned by August 10, 2000

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                                  ATTACHMENT A
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                       DESCRIPTION OF SEPARATION BENEFITS
                       ----------------------------------


In exchange for your signature on the Separation Agreement and Release, the
Company will pay you Thirty Three Thousand, Eight Hundred Dollars and Four Cents
($33,800.04), less all applicable state and federal taxes as separation pay (the
"Separation Pay").  This Separation Pay will be paid in one lump sum eight (8)
days after the date of execution of this letter agreement, provided you have not
revoked acceptance of this letter agreement during the seven (7) day revocation
period.

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