Exhibit 10.2

AMENDMENT NO. 1

TO

REGISTRATION RIGHTS AGREEMENT

AMENDMENT NO. 1 TO REGISTRATION RIGHTS AGREEMENT (this “Amendment”), dated as of
February 8, 2008, made among PAETEC Holding Corp., a Delaware corporation (the
“Company”), and each stockholder of the Company listed on the signature pages
hereof under the heading “Stockholders.”

WITNESSETH:

WHEREAS, pursuant to the Agreement and Plan of Merger, dated as of September 17,
2007, as amended (the “Merger Agreement”), among the Company, McLeodUSA
Incorporated, a Delaware corporation (“McLeodUSA”), and PS Acquisition Corp., a
Delaware corporation, holders of the common stock of McLeodUSA will receive
shares of the common stock, par value $0.01 per share, of the Company (the
“Common Stock”);

WHEREAS, pursuant to the Merger Agreement, the Company has entered into a
registration rights agreement (the “McLeodUSA Registration Rights Agreement”),
dated as of the date hereof, among the Company and certain institutional
investors of McLeodUSA listed on the signature pages thereof under the heading
“Stockholders,” pursuant to which the persons specified therein will be entitled
to certain shelf, demand and piggyback registration rights with respect to the
Common Stock as specified therein; and

WHEREAS, the parties to this Amendment wish to amend the Registration Rights
Agreement, dated as of February 28, 2007 (the “Agreement”), among the Company,
PAETEC Corp., a Delaware corporation and direct wholly-owned subsidiary of the
Company, US LEC Corp., a Delaware corporation and direct wholly-owned subsidiary
of the Company, and each person listed on the signature pages thereof under the
heading “Stockholders,” to facilitate the execution, delivery and performance of
the McLeodUSA Registration Rights Agreement;

NOW, THEREFORE, in consideration of the premises and the mutual covenants and
conditions hereinafter set forth, and for other good and valuable consideration,
the receipt and sufficiency of which are hereby acknowledged, the parties hereby
agree as follows:

1. Effectiveness. This Amendment shall be effective as of the Effective Time, as
such term is defined in the Merger Agreement, provided that, if the Effective
Time shall not occur prior to the termination of the Merger Agreement, this
Amendment shall not become effective and shall be null and void ab initio.

2. Definitions.

(a) Section 1 of the Agreement is hereby amended by adding, in the appropriate
alphabetical order, the following definitions to such Section 1:

“McLeodUSA Registration Rights Agreement” means the Registration Rights
Agreement, dated as of February 8, 2008, among the Company and the other Persons
listed on the signature pages thereof.”

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“Warrant Shelf Registration” means the registration by the Company under the
Securities Act of the offering of Common Stock issuable pursuant to the exercise
of purchase warrants issued by the Company under the PAETEC Communications, Inc.
Agent Incentive Plan, as amended and restated.”

(b) The definition of “Excluded Registration” set forth in Section 1 of the
Agreement is hereby amended and restated in its entirety to read as follows:

“Excluded Registration” means (a) a registration of Common Stock under the
Securities Act pursuant to a registration statement filed (i) on Form S-4 or
Form S-8 or any successor registration forms that may be adopted by the SEC,
(ii) in connection with an exchange offer or an offering of securities solely to
existing stockholders of the Company or employees of the Company or its
subsidiaries or (iii) pursuant to the McLeodUSA Registration Rights Agreement,
(b) a Rule 144A Resale Shelf Registration or (c) a Warrant Shelf Registration.”

3. Amendment to Section 7. Section 7(d) of the Agreement is hereby amended and
restated in its entirety to read as follows:

“(d) In the case of any Underwritten Offering of Registrable Common Shares
initiated by a Demand Stockholder pursuant to Section 3(a), the Company agrees,
if requested in writing by the lead managing underwriters of such Underwritten
Offering, not to effect (or register for sale) any public sale or distribution
of any securities that are Similar Securities for the Company’s own account
during the period beginning seven days before, and ending 90 days (or such
lesser period as may be permitted by such lead managing underwriter) after, the
effective date of the Registration Statement filed in connection with such
registration, except for securities of the Company to be offered for the
Company’s account in such Underwritten Offering. Notwithstanding the foregoing,
the Company may effect a public sale or distribution of Common Stock and other
securities that are Similar Securities for the Company’s own account during the
period described above (i) pursuant to registrations on Form S-4 or S-8 or any
successor registration forms, (ii) as part of any registration of securities for
offering and sale to employees, directors or consultants of the Company pursuant
to any stock plan or other benefit plan arrangement, (iii) pursuant to any
Warrant Shelf Registration or (iv) in an amount that shall not exceed the volume
limitations set forth in Rule 144(e)(1). The Company agrees to use commercially
reasonable efforts to obtain from directors or executive officers of the Company
who holds Common Stock or other securities that are Similar Securities an
agreement not to effect any public sale or distribution of such Similar
Securities (other than any sale under Rule 144) for the account of such director
or executive officer during any period referred to in this Section 7(d), except
as part of any Underwritten Offering contemplated in this Section 7(d).”

4. No Inconsistent Agreements. Section 14 of the Agreement is hereby amended and
replaced in its entirety to read as follows:

“14. No Inconsistent Agreements. The Company shall not after the date of this
Agreement enter into any agreement which is inconsistent with the rights

 

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granted pursuant to this Agreement to the Stockholders holding Registrable
Common Shares. The Stockholders agree for purposes of this Section 14 that
(a) the McLeodUSA Registration Rights Agreement in the form attached hereto as
Exhibit A and (b) a registration rights agreement in customary form relating to
a Rule 144A Resale Shelf Registration shall not be deemed inconsistent with the
rights of the Stockholders hereunder.”

5. Miscellaneous. This Amendment shall not constitute an amendment or
modification of any provision of the Agreement not expressly referred to herein.
Except as expressly set forth in this Amendment, the terms, provisions and
conditions of the Agreement shall remain unchanged and in full force and effect.
This Amendment may be executed in counterparts, all of which shall together
constitute a single agreement.

6. Governing Law. THIS AMENDMENT SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK WITHOUT GIVING EFFECT TO ITS
PRINCIPLES OR RULES OF CONFLICT OF LAWS TO THE EXTENT SUCH PRINCIPLES OR RULES
WOULD REQUIRE OR PERMIT THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION.

 

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IN WITNESS WHEREOF, the parties have executed this Amendment as of the date set
forth in the first paragraph hereof.

 

COMPANY: PAETEC HOLDING CORP. By:  

/s/ Arunas A. Chesonis

Name:   Arunas A. Chesonis Title:  

Chairman, President and Chief

Executive Officer

 

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STOCKHOLDERS:

/s/ Arunas A. Chesonis

Arunas A. Chesonis

 

/s/ Richard T. Aab

Richard T. Aab MELRICH ASSOCIATES, L.P.

/s/ Richard T. Aab

By:   Richard T. Aab Its:   General Partner

 

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