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                                                                    Exhibit 10.6

                      FORM OF COMMON STOCK WARRANT NO. 1

                                NAVISITE, INC.

                             COMMON STOCK WARRANT

                                     No. 1

                               December 15, 2000
                                  __________

THIS COMMON STOCK WARRANT AND ANY SECURITIES ISSUABLE UPON THE EXERCISE OR
CONVERSION OF THIS COMMON STOCK WARRANT HAVE NOT BEEN REGISTERED UNDER THE
SECURITIES ACT OF 1933, AS AMENDED, AND MAY NOT BE TRANSFERRED OR OTHERWISE
DISPOSED OF UNLESS THEY HAVE BEEN REGISTERED UNDER SUCH ACT OR PURSUANT TO AN
EXEMPTION FROM REGISTRATION UNDER SUCH ACT.

                                  __________


                        Warrant to Purchase [  ] Shares
                                of Common Stock

     NaviSite, Inc., a Delaware corporation (the "Company"), hereby certifies
that, for value received, CMGI, Inc., a Delaware corporation ("CMGI"), or any
transferee to whom this warrant (the "Warrant") is properly transferred (the
"Holder"), is entitled, on the terms set forth below, to purchase from the
Company at any time until 5:00 p.m., Boston time, on December 15, 2005 (the
"Expiration Date") [$12,000,000 divided by average of the closing prices per
share on Dec. [8, 11, 12, 13 and 14]] fully paid and nonassessable shares of the
Common Stock, par value $0.01 per share (the "Common Stock"), of the Company, at
a price per share equal to [125% of the average of the closing prices per share
on December 8, 11, 12, 13 and 14], subject to adjustments as provided below (the
"Purchase Price").

     This Warrant is being issued pursuant to the Note and Warrant Purchase
Agreement dated December 12, 2000 between the Company and CMGI (the "Note and
Warrant Purchase Agreement").
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     1.   Exercise of Warrant; Conversion of Warrant; Transfer of Warrant.

          (a)  Exercise of Warrant. At any time prior to 5:00 p.m. on the
               -------------------
Expiration Date, the rights represented by this Warrant may be exercised by the
Holder, in whole or in part, upon surrender of this Warrant to the Company,
together with an executed Notice of Exercise or Conversion, substantially in the
form attached hereto as Exhibit A, at the Company's primary executive office,
                        ---------
with payment by check to the Company of the amount obtained by multiplying the
number of shares of Common Stock with respect to which this Warrant is being
exercised by the Purchase Price.

          (b)  Conversion of Warrant. In addition to, and without limiting, any
               ---------------------
other rights of the Holder hereunder, the Holder may elect to convert this
Warrant, in whole or in part, into shares of Common Stock at any time prior to
5:00 p.m. on the Expiration Date by surrendering this Warrant to the Company,
together with an executed Notice of Exercise or Conversion substantially in the
form attached hereto as Exhibit A, at the Company's primary executive office.
                        ---------
Upon receipt of such notice and surrender of the Warrant by the Holder, or on
such later date as specified in the Notice of Exercise or Conversion, the
Company shall deliver to the Holder within a reasonable time, without payment by
the Holder of any cash or other consideration, that number of shares of Common
Stock computed using the following formula:

          X =  Y(A-B)
               ------
                 A

Where:    X =  the number of shares of Common Stock to be issued to the Holder.


          Y =  the number of shares of Common Stock with respect to which this
               Warrant is being converted.

          A =  the Fair Market Value, as defined below, of one share of Common
               Stock.

          B =  Purchase Price.

               If the Common Stock is traded on the Nasdaq National Market, the
Fair Market Value of one share of Common Stock shall be the closing price quoted
on the Nasdaq National Market, as published in The Wall Street Journal on the
                                               -----------------------
date of determination of Fair Market Value. If the Common Stock is not traded on
the Nasdaq National Market, but is traded on an exchange or over-the-counter,
the Fair Market Value of one share of Common Stock shall be the closing price
quoted on the exchange on which the Common Stock is listed or the average of the
closing bid and asked prices of the Common Stock quoted in the Over-the-Counter
Market Summary, whichever is applicable, on the date of determination of Fair
Market Value. In all other cases, the Fair Market Value of one share of Common
Stock shall be determined in good faith by the Company's Board of Directors (the
"Board").

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          (c)  Partial Exercise. Upon any partial exercise or conversion, the
               ----------------
Company will issue to the Holder a new Warrant for the number of shares of
Common Stock as to which this Warrant was not exercised or converted.

          (d)  Fractional Shares. No fractional shares of Common Stock shall be
               -----------------
issued upon any exercise or conversion of this Warrant. Instead of any
fractional share which would otherwise be issuable upon exercise or conversion,
the Company shall pay a cash amount in respect of each fractional share at a
price equal to an amount calculated by multiplying such fractional share
(calculated to the nearest 1/100th of a share) by the Fair Market Value of a
share of Common Stock on the date of exercise or conversion, as applicable,
minus the Purchase Price. Payment of such amount shall be made in cash or by
check payable to the order of the Holder at the time of delivery of any
certificate or certificates arising upon such exercise or conversion.

          (e)  Taxes. The Company will not be required to pay any tax imposed in
               -----
connection with any transfer involved in the issuance of a Warrant or a
certificate for shares of Common Stock in any name other than that of the Holder
hereof, and in such case, the Company will not be required to issue or deliver
any stock certificate or Warrant until such tax is paid.

          (f)  Transfer of Warrant. Transfer of this Warrant to a third party
               -------------------
shall be effected by execution and delivery of the Notice of Assignment attached
hereto as Exhibit B and surrender of this Warrant for registration of transfer
          ---------
of this Warrant at the primary executive office of the Company, together with
funds sufficient to pay any applicable transfer tax. Upon receipt of the duly
executed Notice of Assignment and the necessary transfer tax funds, if any, the
Company, at its expense, shall execute and deliver, in the name of the
designated transferee or transferees, one or more new Warrants representing the
right to purchase a like aggregate number of shares of Common Stock.

     2.   Antidilution Provisions.

          (a)  Reorganization, Reclassification or Recapitalization of the
               -----------------------------------------------------------
Company. In case of (i) a capital reorganization, reclassification or
-------
recapitalization of the Company's capital stock (other than in the cases
referred to in Section 2(c) hereof), (ii) the Company's consolidation or merger
with or into another corporation in which the Company is not the surviving
entity, or a merger in which the Company is the surviving entity but the shares
of the Company's capital stock outstanding immediately prior to the merger are
converted, by virtue of the merger, into other property, whether in the form of
securities, cash or otherwise, or (iii) the sale or transfer of all or
substantially all of the Company's assets, then, as part of such reorganization,
reclassification, recapitalization, merger, consolidation, sale or transfer,
lawful provision shall be made so that there shall thereafter be deliverable
upon the exercise of this Warrant or any portion thereof (in lieu of or in
addition to the number of shares of Common Stock theretofore deliverable, as
appropriate) and without payment of any additional consideration, the number of
shares of stock or other securities of property to which the holder of the
number of shares of Common Stock which would otherwise have been deliverable
upon the exercise or conversion of this Warrant or

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any portion thereof at the time of such reorganization, reclassification,
recapitalization, consolidation, merger, sale or transfer would have been
entitled to receive in such reorganization, reclassification, recapitalization,
consolidation, merger, sale or transfer. This Section 2(a) shall apply to
successive reorganizations, reclassifications, recapitalizations,
consolidations, mergers, sales and transfers and to the stock or securities of
any other corporation that are at the time receivable upon the exercise or
conversion of this Warrant or any portion thereof. If the per share
consideration payable to the Holder for shares of Common Stock in connection
with any transaction described in this Section 2(a) is in a form other than cash
or marketable securities, then the value of such consideration shall be
determined in good faith by the Board.

          (b)  Splits and Combinations. If the Company at any time or from time
               -----------------------
to time after the date of this Warrant subdivides any of its outstanding shares
of Common Stock into a greater number of shares, the Purchase Price in effect
immediately prior to such subdivision shall be proportionately reduced, and,
conversely, if the outstanding shares of Common Stock are combined into a
smaller number of shares, the Purchase Price in effect immediately prior to such
combination shall be proportionately increased.

          (c)  Reclassifications. If the Company reclassifies or otherwise
               -----------------
changes any of the securities into which this Warrant may be convertible into
the same or a different number of securities of any other class or classes, this
Warrant shall thereafter be convertible into such number and kind of securities
as would have been issuable as the result of such change with respect to the
securities into which this Warrant was convertible immediately prior to such
reclassification or other change and the Purchase Price therefor shall be
appropriately adjusted.

          (d)  Liquidation; Dissolution. If the Company shall dissolve,
               ------------------------
liquidate or wind up its affairs, the Holder shall have the right, but not the
obligation, to exercise this Warrant effective as of the date of such
dissolution, liquidation or winding up. If any such dissolution, liquidation or
winding up results in any cash distribution to the Holder in excess of the
aggregate Purchase Price for the shares of Common Stock for which this Warrant
is exercisable, then the Holder may, at its option, exercise this Warrant
without making payment of such aggregate Purchase Price and, in such case, the
Company shall, upon distribution to the Holder, consider such aggregate Purchase
Price to have been paid in full, and in making such settlement to the Holder,
shall deduct an amount equal to such aggregate Purchase Price from the amount
payable to the Holder.

          (e)  Adjustment Certificates. Upon any adjustment of the Purchase
               -----------------------
Price or the number of shares of Common Stock issuable upon exercise or
conversion of this Warrant, a certificate, signed by (i) the Company's President
and Chief Financial Officer or (ii) any independent firm of certified public
accountants of recognized national standing the Company selects at its own
expense, setting forth in reasonable detail the events requiring the adjustment
and the method by which such adjustment was calculated, shall be mailed to the
Holder at the address set forth in Section 6 hereof and shall specify the
adjusted Purchase Price and the number

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of shares of Common Stock issuable upon exercise or conversion of the Warrant
after giving effect to the adjustment.

          (f)  No Impairment. The Company shall not, by amendment of its
               -------------
Certificate of Incorporation or through any reorganization, recapitalization,
transfer of assets, consolidation, merger, dissolution, issue or sale of
securities or any other voluntary action, avoid or seek to avoid the observance
or performance of any of the terms to be observed or performed hereunder by the
Company, but shall at all times in good faith assist in the carrying out of all
provisions of this Section 2 and in the taking of all such action as may be
necessary or appropriate in order to protect the rights of the Holder against
impairment. The Company shall not be deemed to have avoided or to be seeking to
avoid the observance or performance of any of the terms to be observed or
performed hereunder by issuing securities after the Closing Date for a
consideration per share less than the Purchase Price then in effect.

          (g)  Application. Except as otherwise provided herein, all subsections
               -----------
of this Section 2 are intended to operate independently of one another. If an
event occurs that requires the application of more than one subsection, all
applicable subsections shall be given independent effect.

     3.   Notices of Record Date. In case (a) the Company takes a record of the
holders of the Common Stock for the purpose of entitling them to receive any
dividend or other distribution, or any right to subscribe for or purchase any
shares of stock of any class or any other securities; (b) of any capital
reorganization of the Company, any reclassification of the capital stock of the
Company, any consolidation or merger of the Company with or into another
corporation, or any conveyance of all or substantially all of the assets of the
Company to another corporation; or (c) of any voluntary dissolution, liquidation
or winding-up of the Company; then, in each such case, the Company will mail or
cause to be mailed to each Holder of a Warrant at the time outstanding a notice
specifying, as the case may be, (i) the date on which a record is to be taken
for the purpose of such dividend, distribution or right, and stating the amount
and character of such dividend, distribution or right, or (ii) the date on which
such reorganization, reclassification, consolidation, merger, conveyance,
dissolution, liquidation or winding-up is to take place, and time, if any is to
be fixed, as of which the holders of record of Common Stock (or such other stock
or securities at the time receivable upon the exercise or conversion of the
Warrant) will be entitled to exchange their shares of Common Stock (or such
other stock or securities) for securities or other property deliverable upon
such reorganization, reclassification, consolidation, merger, conveyance,
dissolution, liquidation or winding-up, and, in the case of a reorganization,
consolidation, merger or conveyance, the fair market value of such securities or
other property as determined by the Board. Such notice shall be mailed at least
ten days prior to the date specified therein.

     4.   Replacement of Warrant. Upon receipt of evidence reasonably
satisfactory to the Company of the loss, theft, destruction or mutilation of
this Warrant and (in the case of loss, theft or destruction) upon delivery of an
indemnity agreement in such reasonable amount as the

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Company may determine, or (in the case of mutilation) upon surrender and
cancellation thereof, the Company at its expense, will issue a replacement.

     5.   Transferability of Warrant; No Redemption. This Warrant and all rights
hereunder are freely transferable by the Holder, subject to compliance with
applicable state and federal securities laws. This Warrant shall not be
redeemable by the Company, in whole or in part, at any time.

     6.   Notices. All notices, instructions and other communications given
hereunder or in connection herewith shall be in writing. Any such notice,
instruction or communication shall be sent either (i) by certified mail, return
receipt requested, postage prepaid, (ii) via a reputable nationwide overnight
courier service or (iii) by facsimile (with "answer-back" confirmation), in each
case to the address set forth below. Any such notice, instruction or
communication shall be deemed to have been delivered upon receipt of
confirmation of delivery after it is sent by certified mail, return receipt
requested, postage prepaid, one business day after it is sent via a reputable
nationwide overnight courier service, or upon receipt of confirmation of
delivery of a facsimile.

If to the Company to:          NaviSite, Inc.
                               400 Minuteman Road
                               Andover, MA 01810
                               Attention: General Counsel
                               Facsimile: (978) 688-8100


With a copy to:                Hale and Dorr LLP
                               60 State Street
                               Boston, MA 02109
                               Attention: Mark G. Borden, Esq.
                               Facsimile: (617) 526-5000


If to the Holder to:           CMGI, Inc.
                               100 Brickstone Square
                               Andover, MA 01810
                               Attention: William Williams, II, Esq.
                               Facsimile: (978) 684-3601


With a copy to:                Skadden, Arps, Slate Meagher & Flom LLP
                               One Beacon Street
                               Boston, MA 02108
                               Attention: David T. Brewster, Esq.
                               Facsimile: (617) 573-4822

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Either party may give any notice, instruction or communication in connection
with this Warrant using any other means (including personal delivery or ordinary
mail), but no such notice, instruction or communication shall be deemed to have
been delivered unless and until it is received by the party to whom it was sent.
Either party may change the address to which notices, instructions or
communications are to be delivered by giving the other party to this Warrant
notice thereof in the manner set forth in this Section 6.

     7.   Change; Waiver. This Warrant except by agreement may not be changed,
amended or modified in writing signed by the Company and the Holder.

     8.   No Rights as Stockholder. This Warrant does not entitle the Holder to
any voting rights or other rights as a stockholder of the Company prior to the
exercise of this Warrant.

     9.   Headings. The headings in this Warrant are for purposes of reference
only and shall not be deemed to constitute a part hereof.

     10.  Governing Law. This Warrant is delivered in the State of Delaware and
shall be construed in accordance with and governed by the laws of such state
without regard to its conflicts of laws rules.

Dated: December 15, 2000

                                 NAVISITE, INC.

                                 By:____________________________

                                 Title:_________________________

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<PAGE>

                                                                       EXHIBIT A

                       NOTICE OF EXERCISE OR CONVERSION

TO:  NAVISITE, INC.

     1.   The undersigned hereby elects to receive __________ shares of Common
Stock of NaviSite, Inc., pursuant to the terms of the attached Warrant.

     2.   Method of Exercise (Please initial the applicable blank):

          ___  The undersigned elects to exercise the attached Warrant by means
               of a cash payment, and tenders herewith payment in full for the
               purchase price of the shares being purchased, together with all
               applicable transfer taxes, if any.

          ___  The undersigned elects to convert the attached Warrant by means
               of the conversion provisions of Section 2(b) of the Warrant.

     3.   Please issue a certificate or certificates representing said shares of
Common Stock in the name of the undersigned or in such other name as is
specified below:

                      _________________________________
                                    (Name)
                      _________________________________

                      _________________________________
                                   (Address)

     4.   The undersigned represents that the aforesaid shares of Common Stock
are being acquired for the account of the undersigned for investment and not
with a view to, or for resale in connection with, the distribution thereof and
that the undersigned has no present intention of distributing or reselling such
shares.

          All capitalized terms used but not otherwise defined herein shall have
the meaning ascribed to such terms in the Warrant.

                      _________________________________
                                Name of Holder

                      _________________________________
                      Signature of Authorized Signatory

                      _________________________________
                             Print Name and Title

                      _________________________________
                                     Date

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<PAGE>

                                                                       EXHIBIT B

                                ASSIGNMENT FORM

(To be executed only upon the assignment of the within Warrant)

     FOR VALUE RECEIVED, the undersigned registered Holder of the within Warrant
hereby sells, assigns and transfers unto _____________________, whose address is
___________________ all of the rights of the undersigned under the within
Warrant, with respect to shares of Common Stock (as defined within the Warrant)
of NaviSite, Inc., and, if such shares of Common Stock shall not include all the
shares of Common Stock issuable as provided in the within Warrant, that a new
Warrant of like tenor for the number of shares of Common Stock not being
transferred hereunder be issued in the name of and delivered to the undersigned,
and does hereby irrevocably constitute and appoint _________________ attorney
to register such transfer on the books of NaviSite, Inc. maintained for that
purpose, with full power of substitution in the premises.

Dated:_____________

Signature Guaranteed                ___________________________________

____________________                ___________________________________

                                    By:________________________________
                                       (Signature of Registered Holder)

                                    Title:_____________________________


NOTICE:              The signature to this Notice of Assignment must correspond
                     with the name upon the face of the within Warrant in every
                     particular, without alteration or enlargement or any change
                     whatever.

                     The signature to this Notice of Assignment must be
                     guaranteed by a commercial bank or trust company in the
                     United States or a member firm of the New York Stock
                     Exchange.

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