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                                                                    EXHIBIT 4.44



                    EXERCISABLE ON OR BEFORE, AND VOID AFTER
                    P.M. MINNEAPOLIS TIME, DECEMBER 31, 2005



                                    WARRANTS

                              TO PURCHASE 3,000,000

                            SHARES OF COMMON STOCK OF

                                  WAM!NET, INC.

             (Incorporated under the laws of the State of Minnesota)



                  THIS CERTIFIES that Winstar Credit Corp., a Delaware
corporation ("Holder") or assigns, is the owner of the number of Warrants set
forth above, each of which represents the right to purchase from WAM!NET, Inc.,
a Minnesota corporation ("Company"), at any time after September 29, 2000 and on
or before 5:00 Minneapolis time, December 31, 2005, upon compliance with and
subject to the conditions set forth herein, one share (subject to adjustments
referred to below) of the Common Stock of the Company, par value $.01 per share,
for $.01 per share (such Common Stock (as defined below) or other securities or
property purchasable upon exercise of the Warrants being herein called the
"Shares").

                  This Warrant is subject to the following provisions, terms and
conditions:

                  1. Vesting. The rights of the Holder to the Shares underlying
the Warrants shall vest in the Holder in accordance with Schedule I of the
Securities Purchase Agreement dated as of September 29, 2000 ("Securities
Purchase Agreement"), among the Company, Winstar Communications, Inc. and
Winstar Credit Corp. ("Winstar Sub"). Without limiting the foregoing, to the
extent that the Company does not sell shares of its Class H Convertible
Preferred Stock, $.01 par value ("Class H Preferred Shares") to Winstar Sub in
the amounts set forth in Schedule I to the Securities Purchase Agreement, the
right of Holder to exercise Warrants corresponding to the number of Class H
Preferred Shares not so sold as set forth in such Schedule I (prorated within
the specified amounts in any case in which the total number of Class H Preferred
Shares sold is less than a whole multiple of 10,000 shares of Class H Preferred
Shares) shall terminate and be cancelled.
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                  2. Exercise; Transferability. Subject to Section 1 above, the
rights represented by this Warrant may be exercised by the Holder hereof, in
whole or in part (but not as to a fractional share of Common Stock), by written
notice of exercise delivered to the Company ten (10) days prior to the intended
date of exercise and by the surrender of this Warrant (properly endorsed if
required) at the principal office of the Company and by paying in full, as
provided herein, the purchase price of $.01 per share ("Exercise Price").

                  Payment upon exercise of the rights represented by this
Warrant may be made at the option of the Holder (a) in cash or by certified or
official bank check payable to the order of the Company, (b) by surrendering to
the Company for cancellation and retirement any number Class H Preferred Shares,
which shares shall each be valued for purposes hereof at their Accreted Value
(as defined in the Certificate of Designations for the Class H Preferred Shares)
plus the sum of any then accumulated and unpaid dividends thereon, (c) by
cancellation and discharge of all or any portion of any debt then owed by the
Company to the Holder on a dollar for dollar basis, including principal whether
or not then due and payable together with any interest accrued and unpaid
thereon, or (d) by any combination of any or all of the foregoing.

                  This Warrant may not be transferred or divided into two or
more Warrants of smaller denominations, nor may any Common Stock issued pursuant
to exercise of this Warrant be transferred unless this Warrant or shares have
been registered under the Securities Act of 1933, as amended ("Securities Act"),
and applicable state laws, or unless the Holder of the certificate obtains an
opinion of counsel satisfactory to the Company and its counsel that the proposed
transfer may be effected without registration pursuant to exemptions under the
Securities Act and applicable state laws.

                  3. Issuance of Shares/Warrants. The Company agrees that the
Shares purchased hereby shall be deemed to be issued to the Holder as of the
close of business on the date on which this Warrant shall have been surrendered
and the payment shall have been tendered for such Shares as aforesaid. Subject
to the provisions of the next succeeding paragraph, certificates for the Shares
so purchased shall be delivered to the Holder hereof within a reasonable time,
not exceeding five (5) days after the rights relating to those Shares shall have
been so exercised, and, unless this Warrant has expired, a new Warrant
representing the number of Shares with respect to which this Warrant shall not
then have been exercised and the exercise right shall not have been cancelled in
accordance with Section 1 above, shall also be delivered to the Holder hereof
within such time.

                  Notwithstanding the foregoing, however, the Company shall not
be required to deliver any certificate for Shares which may be issued upon
exercise of this Warrant, except in accordance with the provisions, and subject
to the limitations, of Sections 1, 3 and 8 hereof.

                  Subject to Sections 1, 3 and 8 herein, upon any exercise of
less than all the Warrants evidenced by this Warrant Certificate, there shall
additionally be issued to the Holder a new Warrant Certificate in respect of the
Warrants as to which this Warrant Certificate was not exercised and the exercise
right was not cancelled in accordance with Section 1 above.

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                  4. Covenants of Company. The Company covenants and agrees that
all Shares which may be issued upon the exercise of the rights represented by
this Warrant will, upon issuance, be duly authorized and issued, fully paid,
nonassessable and free from all taxes, liens and charges with respect to the
issue thereof, and without limiting the generality of the foregoing, the Company
covenants and agrees that it will from time to time take all such action as may
be required to assure that the par value per share of the Common Stock is at all
times equal to or less than the then effective purchase price per share of the
Common Stock issuable pursuant to this Warrant. The Company further covenants
and agrees that during the period within which the rights represented by this
Warrant may be exercised, the Company will at all times have authorized, and
reserved for the purpose of issue or transfer upon exercise of the subscription
rights evidenced by this Warrant, a sufficient number of shares of its Common
Stock to provide for the exercise of the rights represented by this Warrant.

                  5. Adjustments. The above provisions are, however, subject to
the following provisions:

                  (a) No fractional shares of Common Stock are to be issued upon
the exercise of the Warrant, but the Company shall pay a cash adjustment in
respect of any fraction of a share which would otherwise be issuable in an
amount equal to the same fraction of the market price per share of Common Stock
on the date of exercise as determined in good faith by the Company.

                  (b) If any capital reorganization or reclassification of the
capital stock of the Company, or consolidation or merger of the Company with
another corporation, or the sale of all or substantially all of its assets to
another corporation shall be effected in such a way that holders of Common Stock
shall be entitled to receive stock, securities or assets with respect to or in
exchange for Common Stock then, as a condition of such reorganization,
reclassification, consolidation, merger or sale, lawful and adequate provision
shall be made whereby the Holder hereof shall hereafter have the right to
purchase and receive upon the basis and upon the terms and conditions specified
in this Warrant and in lieu of the Shares immediately theretofore purchasable
and receivable upon the exercise of the rights represented hereby, such shares
of stock, securities or assets as may be issued and payable with respect to or
in exchange for a number of outstanding shares of such Common Stock equal to the
number of Shares immediately theretofore purchasable and receivable upon the
exercise of the rights represented hereby had such reorganization,
reclassification, consolidation, merger or sale not taken place, and in any such
case appropriate provisions shall be made with respect to the rights and
interests of the Holder of this Warrant to the end that the provisions hereof
(including without limitation provisions for adjustments of the number of Shares
purchasable upon the exercise of this Warrant) shall thereafter be applicable,
as nearly as may be, in relation to any shares of stock, securities or assets
thereafter deliverable upon the exercise hereof. The Company shall not effect
any such consolidation, merger or sale, unless prior to the consummation thereof
the successor corporation (if other than the Company) resulting from such
consolidation, merger, or the corporation purchasing such assets shall assume by
written instrument executed and mailed to the registered Holder hereof at the
last address of such holder appearing on the books of the Company, the
obligation to deliver to such holder such shares of stock, securities or assets
as, in accordance with the foregoing provisions, such holder may be entitled to
purchase.

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                  (c) If the Company shall at any time or from time to time (i)
distribute (otherwise than as a dividend in cash or in Common Stock or
securities convertible into or exchangeable for Common Stock) to the holders of
Common Stock any property or other securities, or (ii) declare a dividend upon
the Common Stock (to the extent payable otherwise than out of earnings or earned
surplus, as indicated by the accounting treatment of such dividend in the books
of the Company, and otherwise than in Common Stock or securities convertible
into or exchangeable for Common Stock), the Company shall reserve and the Holder
of this Warrant shall thereafter upon exercise hereof be entitled to receive,
with respect to each Share of Common Stock purchased hereunder, without any
change in, or payment in addition to, the Exercise Price, the amount of any
property or other securities which would have been distributable to such Holder
had such Holder been a Holder of one share of Common Stock on the record date of
such distribution or dividend (or if no record date was established by the
Company, the date such distribution or dividend was paid).

                  (d) Upon the occurrence of an event giving rise to an
adjustment in the number of shares of Common Stock of the Company into which the
Class H Preferred Shares are convertible pursuant to Section 7 of the Class H
Preferred Shares Certificate of Designation, and in which the shares of Common
Stock or other securities issued or sold by the Company are issued or sold at a
price equivalent to less than $2.50 per share of Common Stock, additional
Warrants shall promptly be issued by the Company to the Holder, or Holders on a
pro-rata basis, in an amount in accordance with subsection 3.3 (b) of the
Securities Purchase Agreement.

                  6. Common Stock. As used herein, the term "Common Stock" means
the Company's presently authorized shares of Common Stock and shall also include
any capital stock of any class of the Company hereafter authorized which shall
not be limited to fixed sum or percentage in respect of the rights of the
holders thereof to participate in dividends or in the distribution of assets
upon the voluntary or involuntary liquidation, dissolution or winding up of the
Company.

                  7. No Voting Rights. This Warrant shall not entitle the Holder
hereof to any voting rights or other rights as a stockholder of the Company.

                  8. Notice of Transfer of Warrant or Resale of Shares. The
Holder of this Warrant, by acceptance hereof, agrees to give written notice to
the Company before transferring this Warrant, or transferring any Common Stock
issued upon the exercise hereof, of such holder's intention to do so, describing
briefly the manner of any proposed transfer. Promptly upon receiving such
written notice the Company shall present copies thereof to the Company counsel
and if in the opinion of such counsel the proposed transfer complies with
federal and state securities laws and may be effected without registration or
qualification (under any Federal or State law), the Company, as promptly as
practicable, shall notify such holder of such opinion, whereupon such holder
shall be entitled to transfer this Warrant or to dispose of shares of Common
Stock received upon the previous exercise of this Warrant, provided that an
appropriate legend may be endorsed on this Warrant or the certificates for such
shares respecting restrictions upon transfer thereof necessary or advisable in
the opinion of counsel to the Company to prevent further transfers which would
be in violation of Section 5 of the Securities Act of 1933.

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                  If in the opinion of Company's counsel referred to in this
Section 8 hereof, the proposed transfer or disposition of shares described in
the written notice given pursuant to this Section 8 may not be effected without
registration or qualification of this Warrant or the shares of Common Stock
issued on the exercise hereof, the Company shall promptly give written notice
thereof to the Holder hereof, and the Holder will limit its activities in
respect to such as, in the opinion of such counsel, are permitted by law.

                  9. Registration Rights. The Holder shall have the registration
rights with respect to shares of Common Stock underlying the Warrants,
regardless of whether the Warrants have been exercised, as are set forth in
Section 8 of the Securities Purchase Agreement.

                  IN WITNESS WHEREOF, WAM!NET, Inc. has caused this Warrant to
be signed by its duly authorized officer and this Warrant to be dated September
29, 2000.



                                             WAM!NET, Inc.


                                             By:  /s/ Terri F. Zimmerman
                                                  ------------------------------
                                                  Terri F. Zimmerman
                                                  Chief Financial Officer

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