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                                                                   EXHIBIT 10.39

               AMENDMENT THREE TO GOODNET NETWORK ACCESS AGREEMENT
                         BETWEEN WINSTAR WIRELESS, INC.
                                       AND
                          ABOVENET COMMUNICATIONS, INC.


        WinStar Wireless, Inc, successor-in-interest to GoodNet, Inc.,
("WinStar") and AboveNet Communications, Inc. ("Customer" or "AboveNet"), agree
that the following terms and conditions of this third amendment and all
attachments hereto (collectively, the "Amendment") amend and/or supplement the
WinStar Network Access Agreement dated June 11, 1996 and any attachments and/or
amendments thereto (collectively and as amended hereby, the "Agreement") between
WinStar and Customer.

        In consideration of the obligations set forth herein and for other good
and valuable consideration, the parties to this Amendment hereby agree as
follows:

                                  GENERAL TERMS

1.      Term. WinStar and the Customer have agreed to extend the term of the
        Agreement by [*] and may be further extended in accordance with the
        provisions of Section 4(c) hereof. WinStar and Customer agree that the
        term of the circuits listed in Attachment A will expire at 11:59 p.m.
        Eastern Time on [*] unless extended in accordance with the provisions of
        Section 4(c) hereof.

2.      Installation. In exchange for installation services performed by
        WinStar, which includes without limitation the installation of base
        circuits as set forth in Attachment A up to and including the date of
        March 31, 1999, and, in consideration for the complexity and cost of
        Circuit installation, AboveNet will pay to WinStar a network Setup and
        Installation fee of [*] which amount will be paid in two installments:
        (i) [*] upon execution hereof; and (ii) [*] on the later of June 30,
        1999 or the date circuits 101, 108 and 111 all have been installed in
        accordance with Section 5 hereof. AboveNet and WinStar agree that
        circuits 102, 104, 107, 109, 110, 112, 113, 114, 115, 117 and 118 were
        installed by March 31, 1999, and that the monthly recurring charges for
        such circuits will commence on April 1, 1999. Monthly recurring charges
        with respect to circuits 101, 108 and 111 will commence upon
        installation in accordance with Section 5 hereof. Circuits 102 and 104
        will be disconnected upon installation of circuits 111 and 108,
        respectively. Section 7 hereof will not apply to the disconnection of
        circuits 102 and 104. All monthly recurring charges will be invoiced in
        advance and paid on net thirty (30) day terms. Charges more than thirty
        (30) days overdue will accrue interest charges at the lesser of 1.5% per
        month or the highest rate permitted by law.


* Certain information on this page has been omitted and filed separately with
  the Commission. Confidential treatment has been requested with respect to the
  omitted portions.



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3.      Volume Credits. In exchange for the volume of services Customer is
        purchasing from WinStar and in order to provide an additional incentive
        (but not the obligation) for Customer to purchase additional circuits
        and related services from WinStar under the Agreement, WinStar will
        provide Customer three separate credits of [*] each, to be applied
        against Customer's total amounts owed to WinStar as follows: (i) one
        such credit on the September, 1999 invoice, (ii) one such credit on the
        September, 2000 invoice and (iii) one such credit on the September, 2001
        invoice. Credit amounts in excess of invoiced charges as of such credit
        month (if any) will be carried forward to and applied against successive
        invoice(s) until the credit amount is used in full.

4.      Pricing.

        (a) WinStar and the Customer have agreed that the current pricing for
        the circuits as stated in Attachment A to this Amendment will remain
        fixed until March 31, 2002.

        (b) On or before the 60th day prior to March 31, 2002, AboveNet may
        request that the parties meet to discuss the pricing provided under this
        Agreement after such date. If the pricing for the monthly recurring
        charges is materially above WinStar's then current market rate for a
        customer purchasing similar or higher volume of the same type of
        services as provided to Customer by WinStar, Attachment A will be
        amended to state revised pricing that reflects WinStar's then current
        market rate for such services being provided by WinStar to similarly
        situated business customers (or competitive rates for such services if
        there are no such similarly situated business customers at that time).
        WinStar and AboveNet will negotiate in good faith to agree on the terms
        of an such an amendment to Attachment A; provided, however, that if the
        parties have not agreed to a mutually satisfactory revised pricing
        within 30 days after the AboveNet request, AboveNet may deliver within
        thirty (30) days thereafter a notice to WinStar of disputed pricing
        which notice shall include the name of two major national long distance
        telecommunications service carriers to be contacted regarding
        alternative pricing. Upon receipt of such notice WinStar shall select a
        nationally recognized accounting firm (which shall not be the accounting
        firm used by WinStar as its independent certified public accountant) who
        shall then solicit bids on a confidential basis on the circuits listed
        on Attachment A (other than circuits 102 and 104) from the carriers
        identified by AboveNet and two additional major national long distance
        telecommunications carriers selected by WinStar. Said accountant shall
        then determine the median price for such circuits from such carriers and
        an adjustment shall be made in the then applicable pricing to reflect
        the median pricing. The cost of such accountant's services shall be
        split equally and paid by the parties.


* Certain information on this page has been omitted and filed separately with
  the Commission. Confidential treatment has been requested with respect to the
  omitted portions.



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        (c) On or before the sixtieth (60th) day prior to September 30, 2003 and
        the end of each eighteen (18) month period thereafter during which the
        Agreement is in effect, either party may request that the parties meet
        to discuss the then current pricing provided under this Agreement.
        WinStar and AboveNet will negotiate in good faith to agree on pricing
        for the succeeding eighteen (18) month period. If WinStar and AboveNet
        are able to reach agreement on mutually satisfactory pricing for such
        period, the Agreement shall be extended for an additional eighteen (18)
        month period from the then current expiration date. If the parties are
        unable to reach mutual agreement with respect to satisfactory pricing
        for the succeeding eighteen (18) month period, the then current pricing
        will remain in effect until the expiration of the Agreement on the then
        current expiration date.

5.      Circuit Installation. Each of the Circuits referred to in Attachment A
        have been accepted by Customer as installed except for Circuits 101, 108
        and 111. With respect to Circuits 101, 108 and 111, each of such
        circuits shall be deemed installed when the Circuit (i) has been
        operating continuously for twenty-four (24) hours without interruption
        with a 10E-9 BER (Bit Error Rate); and (ii) has satisfied the minimum
        round-trip latency specifications set forth in Schedule B. WinStar will
        notify Customer at such time that it deems the Circuit to have satisfied
        the criteria set forth in (i) and (ii) above and such Circuit shall be
        deemed accepted unless Customer demonstrates that the Circuit has not
        met such criteria and notified WinStar within five (5) days after
        WinStar's notice of completion of installation. Each of the parties will
        act in good faith to expedite completion of the installation of the
        Circuits.

        A circuit ordered by Customer in the future will be deemed to be
        accepted by Customer when the end to end circuit from the locations set
        forth in the Service Order are determined by WinStar and Customer to
        operate in a manner that satisfies the specifications and testing
        criteria contained in the Service Order entered into by WinStar and
        Customer with respect to such Circuit. Customer's obligation to pay for
        future circuits provided under this Agreement shall commence upon
        completion of installation of such circuits by WinStar (i.e., when such
        circuits are made available for use for the Customer and meet the
        installation criteria set forth in the service order). WinStar will not
        be responsible for inside wiring and building easements of a connection
        beyond the demarcation point of presence (POP) of the service, unless
        otherwise specified in the Service Order.

6.      Portability. WinStar will use commercially reasonable efforts to
        accommodate Customer's request for exchange, replacement or change-out
        of circuits at the same level that are on WinStar's network. AboveNet
        agrees that it shall be responsible for paying all additional third
        party costs that WinStar incurs for making such changes (including
        without limitation WinStar's additional supplier costs, if any). In such
        event, the parties will negotiate alternate pricing for the new circuits
        which reflects the pricing and economics of this Agreement for
        equivalent circuits but shall not reduce the payments required
        hereunder. Section 7 hereof will not apply to the old circuit that is
        being exchanged, replaced or changed-out by a new circuit pursuant to
        this Section 6.

7.      Underutilization Fee. In the event that Customer terminates service
        prior to the end of the term for any circuit, then, except as
        specifically set forth in Sections 2 and 6 hereof, Customer agrees to
        pay an underutilization fee charge equal to fifty percent (50%) of the




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        monthly recurring charges for the terminated circuit, multiplied by the
        number of months remaining in the term for that circuit. Customer and
        WinStar acknowledge that the underutilization fee is a liquidated damage
        and not a penalty and each party further acknowledges that the charges
        for the services hereunder would be substantially higher but for this
        provision.

8.      Entire Agreement. This Amendment and the Agreement as modified hereby
        constitutes the entire agreement between the parties and supersedes any
        and all prior or contemporaneous agreements whether written or oral. In
        the event of a conflict between this Amendment and the Agreement or any
        other prior attachments, the terms of this Amendment shall prevail. The
        parties specifically agree that this Amendment supercedes the previous
        Amendment Nos. 1 and 2 to the Agreement, and Attachment ID# 980410G each
        of which is in all respects terminated and of no further force and
        effect including, without limitation, all previously accrued credits and
        credit obligations of any type in favor of Customer under the Agreement.
        This Agreement cannot be modified except in writing signed by authorized
        officers of both parties.

9.      Assignment. Each party agrees that no person will be permitted to
        acquire substantially all of such party's assets unless the acquiring
        person agrees to be bound by all of the provisions of this Agreement
        binding on such party.


        IN WITNESS WHEREOF, the parties have caused this Amendment to be
executed by their respective duly authorized representatives on the date set
forth below:




AboveNet Communications                 WinStar Wireless, Inc.

By:                                     By:
   --------------------------------        -------------------------------------

Name:                                   Name:
    -------------------------------         ------------------------------------


Title:                                  Title:
     ------------------------------          -----------------------------------


Date:                                   Date:
     ------------------------------          -----------------------------------



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                                     REVISED
                                  ATTACHMENT A

<TABLE>
<CAPTION>
                                                             MONTHLY
                                                            RECURRING
                     CIRCUIT                                 CHARGE
               -------------------                          ---------
<S>                                                         <C>  
               ABO-101-MAE-MAW-OC3                            $ [*]
               ABO-102-SJC-POR-DS3                            $ [*]
               ABO-104-SJC-LOS-DS3                            $ [*]
               ABO-107-SJC-SEA-DS3                            $ [*]
               ABO-108-SJC-LOS-OC3                            $ [*]
               ABO-109-SJC-CHI-OC3                            $ [*]
               ABO-110-MAE-CHI-OC3                            $ [*]
               ABO-111-SJC-POR-OC3                            $ [*]
               ABO-112-DAL-CHI-DS3                            $ [*]
               ABO-113-DAL-LOS-DS3                            $ [*]
               ABO-114-MAE-PAX-OC3                            $ [*]
               ABO-115-MAE-MAW-OC12                           $ [*]
               ABO-117-MAE-SPN-OC3                            $ [*]
               ABO-118-SEA-POR-DS3                            $ [*]
</TABLE>



* Certain information on this page has been omitted and filed separately with
  the Commission. Confidential treatment has been requested with respect to the
  omitted portions.

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                                   SCHEDULE B
                  LATENCY COMMITMENTS-CIRCUITS 101, 108 AND 111


        For purposes of determining whether the latency specifications have been
satisfied, the parties agree that the round-trip latency should not be greater
than the current round-trip latency set forth below as the "Latency
Specification":

<TABLE>
<CAPTION>
         Circuit                                         Latency Specification
         -------                                         ---------------------
<S>                                                       <C> 
     101 MAE-E-MAE-W                                              [*]
     111 SJC-POR-OC3                                              [*]
     108 LOS-SJC-DS3                                              [*]
</TABLE>

        AboveNet agrees to cooperate with WinStar in determining the applicable
latency measurements on the Circuits and will assist WinStar by conducting
latency testing of such Circuits at such times as reasonably requested by
WinStar and will, if requested by WinStar, permit a WinStar representative to
participate in such testing.


*Certain information on this page has been omitted and filed separately with
 the Commission. Confidential treatment has been requested with respect to the 
 omitted portions.


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