FOURTH AMENDMENT TO THE RIGHTS AGREEMENT

                  THIS FOURTH AMENDMENT TO THE RIGHTS AGREEMENT, made and
entered into as of this 6th day of December, 2000 (this "Fourth Amendment"), by
and between WINSTAR COMMUNICATIONS, INC. (the "Company") and CONTINENTAL STOCK
TRANSFER AND TRUST COMPANY, as Rights Agent (the "Rights Agent"), is being
executed under the following circumstances:

                  WHEREAS, the Company and the Rights Agent entered into a
Rights Agreement, dated as of July 2, 1997, an Amendment to the Rights
Agreement, dated as of June 3, 1999, a Second Amendment to the Rights Agreement,
dated as of July 15, 1999, and a Third Amendment to the Rights Agreement, dated
as of January 31, 2000 (as so amended, the "Rights Agreement");

                  WHEREAS, effective July 2, 1997 (the "Rights Dividend
Declaration Date") the Board of Directors of the Company authorized and declared
a distribution of one Right (each, a "Right") for each share of Common Stock,
par value $.01 per share, of the Company (the "Company Common Stock")
outstanding at the Close of Business (as defined in the Rights Agreement) on
July 14, 1997 (the "Record Date"), and authorized the issuance of one right (as
such number may be adjusted pursuant to the Rights Agreement) for each share of
Company Common Stock issued between the Record Date (whether originally issued
or delivered from the Company's treasury) and, except as otherwise provided in
Section 22 of the Rights Agreement, the Distribution Date, each Right initially
representing the right to purchase upon the terms and subject to the conditions
set forth in the Rights Agreement one Unit (as defined in the Rights Agreement)
of Series B Preferred Stock (as defined in the Rights Agreement); and

                  WHEREAS, the Board of Directors of the Company, by resolutions
duly adopted on December 1, 2000, authorized this Fourth Amendment to the Rights
Agreement in accordance with Section 26 of the Rights Agreement.

                  NOW THEREFORE, the Company and the Rights Agent hereby amend
the Rights Agreement as follows, pursuant to Section 26 of the Rights Agreement:

                  Section 1.    Amendments to the Rights Agreement.  (a)  The
following definitions shall be added to Section 1 of the Rights Agreement, in
appropriate alphabetical order:

                  ""December 2000 Warrants" shall mean the Warrants to purchase
                  shares of Common Stock of the Company issued by the Company
                  concurrently with the issuance of the Series H Preferred
                  Stock."

                  ""Series G Preferred Stock" shall mean the Company's Series G
                  Senior Cumulative Participating Convertible Preferred Stock."



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                  ""Series H Preferred Stock" shall mean the Company's Series H
                  Senior Cumulative Participating Convertible Preferred Stock."

The definitions set forth in Section 1 of the Rights Agreement shall be
appropriately renumbered to reflect the addition of the definitions for the
December 2000 Warrants, the Series G Preferred Stock and the Series H Preferred
Stock.

                  (b) Clause (D) of the proviso set forth at the end of Section
1(e) of the Rights Agreement shall be deleted in its entirety and replaced with
the following:

                  "(D) either (x) any shares of a class of Voting Stock
                  represented by shares of Series G Preferred Stock, Series H
                  Preferred Stock or the December 2000 Warrants Beneficially
                  Owned by such Person on December 6, 2000, to the extent, but
                  only to the extent, that such Beneficial Ownership would, but
                  for this clause (x), result in such Person being an Acquiring
                  Person hereunder, provided that such Person does not after
                  December 6, 2000 acquire in any manner whatsoever the
                  Beneficial Ownership of any shares of a class of Voting Stock
                  other than as provided by clause (y) immediately following
                  hereafter, or (y) any shares of a class of Voting Stock either
                  issued or deemed issued by the Company in payment of dividends
                  on, or as a result of the failure of the Company to pay cash
                  dividends on, outstanding shares of Series G Preferred Stock
                  or Series H Preferred Stock pursuant to the terms of the
                  instruments providing for the creation of the Series G
                  Preferred Stock and the Series H Preferred Stock."

                  Section 2. Full Force and Effect.  The remainder of the Rights
Agreement shall remain unchanged, and the Rights Agreement, as amended above,
shall remain in full force and effect.

                  Section 3. Governing Law.  This Fourth Amendment shall be
governed by, and construed in accordance with, the laws of the State of
Delaware.

                  Section 4. Counterparts. This Fourth Amendment may be executed
in two or more counterparts and each of such counterparts shall for all purposes
be deemed to be an original and all such counterparts shall constitute but one
and the same instrument. Delivery of an executed counterpart of a signature page
to this Fourth Amendment by telecopier shall be as effective as delivery of a
manually executed counterpart of this Fourth Amendment.

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                  IN WITNESS WHEREOF, the parties hereto have caused this Fourth
Amendment to be duly executed on their behalf as of the date first above
written.

                                 WINSTAR COMMUNICATIONS, INC.


                                 By:   /s/ Kenneth J. Zinghini
                                      ------------------------------
                                      Name:   Kenneth J. Zinghini
                                      Title:  Senior Vice President


                                 CONTINENTAL STOCK TRANSFER
                                 & TRUST COMPANY


                                 By:   /s/ Steven Nelson
                                      -------------------------------
                                      Name:  Steven Nelson
                                      Title: Chairman



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