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                                                                  Exhibit 10.7.2

                   FIRST AMENDMENT TO STOCK RIGHTS AGREEMENT


          This is an Amendment to Stock Rights Agreement (the "Amendment"),
dated September 30, 1998, between TIMOTHY J. BANCROFT ("Shareholder"), PAETEC
CORP., a Delaware corporation with its principal place of business at 290
Woodcliff Drive, Fairport, New York 14450 (the "Company"), PAETEC
COMMUNICATIONS, INC., a Delaware corporation and wholly-owned subsidiary of the
Company with its principal place of business at 290 Woodcliff Drive, Fairport,
New York 14450 ("Subsidiary"), and ARUNAS A. CHESONIS ("Founder").

                                   RECITALS

          A.  Shareholder holds 5,000 shares of Class B common stock of the
Company, subject to certain restrictions contained in a Stock Rights Agreement,
dated August 13, 1998, among the parties (the "Agreement").

          B.  The Company has now offered to issue to Shareholder 5,000 shares
of Class A common stock at a purchase price of $2.50 per share, subject to
certain restrictions.

          C.  The Company, Subsidiary, Shareholder, and Founder enter into this
Amendment for the purpose of confirming Shareholder's equity interest in the
Class A common stock of the Company and outlining the rights of Shareholder and
the restrictions imposed by the Company with respect to the Class A common stock
to be held by Shareholder.

                                     TERMS

          NOW, THEREFORE, in consideration of the following mutual promises, the
parties agree as follows:

          1.  Issuance of Shares.  The Company confirms its offer to issue 5,000
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shares of Class A common stock (the "Class A Shares") to Shareholder at a price
of $2.50 per share, payable in full upon issuance of the Class A Shares.  A
stock certificate evidencing the Class A Shares shall be issued in the name of
Shareholder upon receipt of this executed Amendment and payment in full of the
purchase price.

          2.  Incorporation of Agreement by Reference.  Section 6 of the
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Agreement ("Stockholders' Agreement and Proxy") shall not apply to the Class A
Shares issued to Shareholder pursuant to this Amendment.  All other provisions
of the Agreement shall apply to the Class A Shares issued to Shareholder
pursuant to this Amendment, except to the extent that a provision of this
Amendment expressly supersedes any provision of the Agreement.
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          3.  Legends.  Each certificate for Class A Shares owned by Shareholder
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shall bear the following legends:

              (a)   The shares represented by this certificate were issued to
          the shareholder with restrictions. Neither the shares, nor any
          interest in them, may be sold, transferred, assigned, pledged,
          hypothecated, or otherwise disposed of, unless that transfer is
          expressly permitted by a stock rights agreement, including any
          amendment thereto, between the shareholder and the Company, a copy of
          which is on file at the office of the Company in Fairport, New York.

               (b)  The shares represented by this certificate have not been
          registered under the Securities Act of 1933, as amended, and may not
          be transferred in the absence of such registration unless the Company
          receives an opinion of counsel reasonably acceptable to it stating the
          such sale or transfer is exempt from registration.

With respect to Class A Shares that are subject to the Company's Purchase
Option, described in Section 4 of the Agreement, however, Shareholder shall be
entitled to a certificate without the legend set forth in subparagraph (a),
evidencing any Class A Shares as to which the Purchase Option has expired.

          The parties' assent to the terms of this Agreement is confirmed by
their signatures below.

                                        PAETEC CORP.



                                        By: /s/ Arunas A. Chesonis
                                           -------------------------------
                                             Title: President


                                        PAETEC COMMUNICATIONS, INC.



                                        By: /s/ Arunas A. Chesonis
                                           -------------------------------
                                             Title: President

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Address:                                /s/ Timothy J. Bancroft
                                        -------------------------------
                                            Timothy J. Bancroft
35 Little Spring Run
Fairport, New York 14450


Address:                                /s/ Arunas A. Chesonis
                                        -------------------------------
                                            Arunas A. Chesonis
18 Buckthorn Run
Victor, New York 14564

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