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                                                                    EXHIBIT 10.3

                                                                  EXECUTION COPY

                                SECOND AMENDMENT

            SECOND AMENDMENT, dated as of May 5, 2004 (the "SECOND AMENDMENT"),
to the THIRD AMENDED AND RESTATED CREDIT AGREEMENT, dated as of September 13,
2002, as amended by the Letter Amendment and Waiver dated as of November 12,
2002 (as so amended, the "CREDIT AGREEMENT"), by and among CHOICE ONE
COMMUNICATIONS, INC., as Guarantor, certain of its Subsidiaries, as Borrowers,
the Lenders party thereto, WACHOVIA INVESTORS, INC., as Administrative Agent and
Collateral Agent, GENERAL ELECTRIC CAPITAL CORPORATION, as Syndication Agent,
and MORGAN STANLEY SENIOR FUNDING, INC., as Documentation Agent. Capitalized
terms not otherwise defined in this Second Amendment have the same meanings as
specified in the Credit Agreement.

                             PRELIMINARY STATEMENTS

            WHEREAS, Wachovia Investors, Inc. is currently the Administrative
Agent under the Credit Agreement and the Collateral Agent under the Security
Documents but is willing to resign in such capacities if the Required Lenders
desire to appoint General Electric Capital Corporation as successor
Administrative Agent and successor Collateral Agent;

            WHEREAS, the Required Lenders desire to appoint General Electric
Capital Corporation as, and General Electric Capital Corporation agrees to
become, successor Administrative Agent and successor Collateral Agent; and

            WHEREAS, the Required Lenders, the Guarantor and the Borrowers have
agreed to amend certain provisions of the Credit Agreement to reflect the
foregoing and certain other matters.

            NOW THEREFORE, the parties hereto hereby agree as follows:

            Section 1. Amendments to the Credit Agreement. The Credit Agreement
is, effective as of the Effective Date (as defined in Section 4 below), hereby
amended as follows:

            (a)   The recital of parties is amended to read In full as follows:

            "This THIRD AMENDED AND RESTATED CREDIT AGREEMENT, dated as of
            September 13, 2002, by and among CHOICE ONE COMMUNICATIONS INC., a
            Delaware corporation, as Guarantor, its Subsidiaries listed on the
            signature pages hereto and any additional Subsidiaries joined
            hereto, as Borrowers, the Lenders who are or may become a party to
            this Agreement, GENERAL ELECTRIC CAPITAL CORPORATION, as
            Administrative Agent and Collateral Agent (successor to Wachovia
            Investors, Inc. in such capacities) and as Syndication Agent, and
            MORGAN STANLEY SENIOR FUNDING, INC., as Documentation Agent,"

            (b)   Section 1.1 is amended to add the following new definition in
the appropriate alphabetical order:

                  ""GECC" means General Electric Capital Corporation and its
successors,"

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            (c)   The definition of "Administrative Agent" in Section 1.1 is
amended by deleting the word "Wachovia" therein and substituting therefor the
word "GECC".

            (d)   The definition of "Collateral Agent" in Section 1.1 is amended
by deleting the word "Wachovia" therein and substituting therefor the word
"GECC".

            (e)   The definition of "Eligible Assignee" in Section 1.1 is
amended by adding the following proviso immediately prior to the period at the
end thereof:

";provided, however, that without the prior written consent of the
Administrative Agent and the Company in their sole discretion, no competitor (or
any Affiliate of a competitor if the Affiliate is not already a Lender
hereunder) of the Company or the Borrowers shall qualify as an Eligible Assignee
under this definition".

            (f)   The definition of "Issuing Lender" in Section 1.1 is amended
to read in full as follows: "[Intentionally deleted]".

            (g)   The definition of "Prime Rate" in Section 1.1 is amended to
read in full as follows:

            "Prime Rate" means, for any day, a floating rate equal to the rate
publicly quoted from time to time by The Wall Street Journal as the "prime rate"
(or, if The Wall Street Journal ceases quoting a prime rate, the highest per
annum rate of interest published by the Federal Reserve Board in Federal Reserve
statistical release H.l5 (519) entitled "Selected Interest Rates" as the Bank
prime loan rate or its equivalent). Each change in Prime Rate shall be effective
as of the opening of business on the day such change in the Prime Rate occurs.

            (h)   Section 5.3 is amended to read in full as follows;

"In order to compensate the Agents with respect to the Credit Facility, the
Borrowers agree to pay to GECC the fees set forth in the separate fee letter
agreement executed by the Company and addressed to GECC with respect to the
Credit Facility dated April 19, 2004."

            (i)   Section 13.1 is amended by deleting all references to
"Wachovia" therein and substituting in each case therefor the word "GECC".

            (j)   Section 13.2(b) is amended in full to read as follows:

"GECC may delegate any or all of its powers and duties as Administrative Agent
or Collateral Agent hereunder and under the other Loan Documents to affiliates
or other agents as agreed to by such Persons."

            (k)   Section 15. l(c) is amended by deleting the following:

      "If to Wachovia, as    Wachovia Investors, Inc.
      Administrative Agent:  Charlotte Plaza CP-23
                             201 South College Street
                             Charlotte, North Carolina 28288-0680
                             Attention: John McGowan
                             Telephone No.: (704) 374-7096
                             Telecopy No.: (704) 383-6249"

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            and substituting therefor the following:

      "If to GBCC, as        General Electric Capital Corporation
      Administrative Agent:  201 Merritt 7
                             P.O. Box 5201 ,
                             Attention: Christopher Nicholls/Christian Donohue
                             Telephone No.: 203-956-4768/203-956-4755
                             Telecopy No.: 203-956-4543/203-956-4559"

            (1)   Section 15.10(f) is amended by deleting the words "banks or
other entities" in the first sentence thereof and substituting therefor the
words "Eligible Assignees".

            Section 2. Amendments to the other Loan Documents. Each other Loan
Document is, effective as of the Effective Date, hereby amended to delete each
reference therein to Wachovia Investors, Inc. as Administrative Agent or as
Collateral Agent and to substitute therefor a reference to General Electric
Capital Corporation as Administrative Agent or Collateral Agent, as the case may
be.

            Section 3. Resignation of Wachovia Investors. Inc. as Administrative
Agent and as Collateral Agent & Transition. (a) Concurrently with the occurrence
of the Effective Date, Wachovia Investors, Inc. hereby gives notice to the
Lenders, the Guarantor and the Borrowers, pursuant to and in accordance with
Section 13.9 of the Credit Agreement, that it is resigning as Administrative
Agent and as Collateral Agent under the Credit Agreement and under the other
Loan Documents, Effective as of the Effective Date, General Electric Capital
Corporation shall succeed to and assume Wachovia Investors, Inc.'s
responsibilities and obligations as Administrative Agent and as Collateral Agent
and shall be vested with all rights, powers, privileges and duties of the
Administrative Agent and the Collateral Agent under the Loan Documents and
Wachovia Investors, Inc. shall be fully released and discharged from all of such
responsibilities and obligations. Without limiting the foregoing, all grants of
security interests and rights of setoff against the Borrowers, or the respective
properties of the Borrowers, and the Guarantor under the Loan Documents granted
prior to the Effective Date in favor of Wachovia Investors, Inc, as
Administrative Agent or Collateral Agent, shall on and after the Effective Date
be deemed to be grants of security interests and rights of setoff in favor of
GECC, in its capacity as successor Administrative Agent or successor Collateral
Agent, as the case may be, under the Loan Documents.

            (b)   Notwithstanding anything otherwise contained herein, it is
understood and agreed that (a) in accordance with Section 13.9 of the Credit
Agreement, the provisions of Article XIII and Section 15.2 of the Credit
Agreement shall continue in effect for the benefit of Wachovia Investors, Inc.
in respect of any actions taken or omitted to be taken by it while it was acting
as Administrative Agent or Collateral Agent and in respect of all actions taken
or omitted to be taken by Wachovia Investors, Inc. pursuant to Subsection 3(c)
below, regardless of whether such acts or omissions shall have occurred before
or after the Effective Date and (b) from and after the Effective Date, such
provisions shall be in effect for the benefit of GECC in respect of all actions
taken or omitted to be taken by it while acting as Administrative Agent or
Collateral Agent.

            (c)   In order to evidence or give public notice of the change in
identity of the Administrative Agent and Collateral Agent, Wachovia Investors,
Inc. (i) agrees to execute and deliver such assignments or amendments to deeds
of trust or mortgages, if any, intellectual property filings, if any, and other
documents as the successor Administrative Agent and successor Collateral Agent
may reasonably request to evidence the transfer of the role of the
Administrative Agent and Collateral Agent from Wachovia Investors, Inc. to
General Electric Capital Corporation, and (ii) authorizes the General Electric
Capital Corporation, as successor Administrative Agent and successor Collateral
Agent, to file or cause to be filed all Uniform Commercial Code financing
statement amendments in connection therewith,

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in each case at the sole cost and expense of the Borrowers. In addition,
Wachovia Investors, Inc. agrees to promptly deliver to General Electric Capital
Corporation, as successor Administrative Agent and successor Collateral Agent,
all promissory notes, stock certificates and other collateral in its possession,
if any, with all instruments of transfer or stock powers delivered in connection
therewith, and until such delivery is effected, acknowledges that it is
retaining control over such notes, stock certificates and other collateral on
behalf of the successor Collateral Agent. The Borrowers and the Guarantor
acknowledge and agree that the change in the Administrative Agent and the
Collateral Agent shall not affect in any manner the creation, perfection or
priority of any Liens previously or hereafter granted to the Administrative
Agent or the Collateral Agent under the Loan Documents, and agree to give,
execute, deliver, file and/or record any notice, statement, instrument document,
agreement or other papers that may be necessary or desirable, or that the
successor Administrative Agent or successor Collateral Agent may reasonably
request, in order to evidence the change in the Administrative Agent and the
Collateral Agent. Without limiting the foregoing, the Borrowers, the Guarantor
and Wachovia Investors, Inc. agree to cooperate with the successor
Administrative Agent and the successor Collateral Agent in contacting insurance
companies providing insurance to the Borrowers or the Guarantor for the purpose
of notifying them and obtaining acknowledgments from them of the designation of
the successor Collateral Agent and the successor Administrative Agent, as the
case may be, as the now loss payee. The Borrowers agree that all costs and
expenses of the activities referred to in this Section 3, including, but not
limited to, the costs of document preparation and filing, shall be borne by the
Borrowers.

            Section 4. Conditions to Effectiveness. This Second Amendment shall
become effective on May 5, 2004 (the "EFFECTIVE DATE") only if Wachovia
Investors, Inc. shall have notified the parties hereto that it has received
counterparts on or before May 5, 2004 of this Second Amendment executed by the
Guarantor, the Borrowers and the Required Lenders or, as to any of the Lenders,
advice satisfactory to Wachovia Investors, Inc. that such Lender has executed
this Second Amendment.

            Section 5. Reference to and Effect on the Loan Documents: etc. (a)
On and after the Effective Date of this Second Amendment, each reference in the
Credit Agreement to "this Agreement", "hereunder", "hereof" or words of like
import referring to the Credit Agreement, and each reference in the Notes and
each of the other Loan Documents to "the Credit Agreement", "thereunder",
"thereof" or words of like import referring to the Credit Agreement, shall mean
and be a reference to the Credit Agreement, as amended by this Second Amendment.

            (b)   The Credit Agreement, the Notes and each of the other Loan
Documents, as specifically amended by this Second Amendment, are and shall
continue to be in full force and effect and are hereby in all respects ratified
and confirmed. Without limiting the generality of the foregoing, the Collateral
Documents and all of the Collateral described therein do and shall continue to
secure the payment of all Obligations of the Loan Parties under the Loan
Documents, in each case as amended by this Second Amendment.

            (c)   The execution, delivery and effectiveness of this Second
Amendment shall not, except as expressly provided herein, operate as a waiver of
any right, power or remedy of any Lender or any Agent under any of the Loan
Documents, nor constitute a waiver of any provision of any of the Loan
Documents.

            (d)   The Borrowers and the Guarantor jointly and severally agree to
promptly pay all reasonable expenses of Wachovia Investors, Inc. and General
Electric Capital Corporation in connection with the preparation, execution and
delivery of this Second Amendment (as well as all outstanding invoices of
professionals retained by the Administrative Agent) and matters related thereto.

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            Section 6. Execution in Counterparts. This Second Amendment may be
executed in any number of counterparts and by different parties hereto in
separate counterparts, each of which when so executed shall be deemed to be an
original and all of which taken together shall constitute but one and the same
agreement. Delivery of an executed counterpart of a signature page to this
Second Amendment by facsimile shall be effective as delivery of a manually
executed counterpart of this Second Amendment.

            Section 7. Governing Law. THIS SECOND AMENDMENT SHALL BE GOVERNED
BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

                     [Remainder of page intentionally blank]

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            IN WITNESS WHEREOF, the parties hereto have caused this Second
Amendment to be executed by their respective officers thereunto duly authorized,
as of the date first above written.

                             BORROWERS:

                             CHOICE ONE COMMUNICATIONS OF NEW YORK INC.
                             CHOICE ONE COMMUNICATIONS OF PENNSYLVANIA INC.
                             CHOICE ONE COMMUNICATIONS OF MASSACHUSETTS INC.
                             CHOICE ONE COMMUNICATIONS INTERNATIONAL INC.
                             CHOICE ONE COMMUNICATIONS OF RHODE ISLAND INC.
                             CHOICE ONE COMMUNICATIONS OF CONNECTICUT INC.
                             CHOICE ONE COMMUNICATIONS OF MAINE INC.
                             CHOICE ONE OF NEW HAMPSHIRE INC.
                             CHOICE ONE COMMUNICATIONS OF OHIO INC.
                             CHOICE ONE COMMUNICATIONS OF VERMONT INC.
                             CHOICE ONE ONLINE INC.
                             CHOICE ONE COMMUNICATIONS OF VIRGINIA INC.
                             CHOICE ONE COMMUNICATIONS SERVICES INC.
                             US XCHANGE INC.
                             US XCHANGE OF INDIANA, L.L.C.
                             US XCHANGE OF ILLINOIS, L.L.C.
                             US XCHANGE OF WISCONSIN, L.L.C.
                             US XCHANGE OF MICHIGAN, L.L.C.

                             By: /s/ Ajay Sabherwal
                                 -----------------------------------
                                     Name: Ajay Sabherwal
                                     Title: EVP & CFO
                                     for each of  the entities set forth above

                             GUARANTOR:

                             CHOICE ONE COMMUNICATIONS INC.
                             By: /s/ Ajay Sabherwal
                                 -----------------------------------
                                     Name: Ajay Sabherwal
                                     Title: EVP & CFO

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                             GOLDMAN SACHS CREDIT PARTNERS, L.P.,
                             as Lender

                             By: /s/ Pedro Ramirez
                                -----------------------------------
                                     Name: Pedro Ramirez
                                     Title:

                             SCOGGIN CAPITAL MANAGEMENT, LP II, as
                             Lender

                             By: /s/ Craig Effron
                                -----------------------------------
                                     Name: Craig Effron
                                     Title: President

                             STRATEGIC VALUE MASTER FUND, LTD, as
                             Lender

                             BY: /s/  Vivianne Hernandez
                                -----------------------------------
                                     Name: Vivianne Hernandez
                                     Title: Authorized Signatory

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                             BANK OF AMERICA, N.A., as Lender

                             By: /s/ Laura T. Sweet
                                -----------------------------------
                                     Name: Laura T. Sweet
                                     Title: Assistant Vice President

                             CARGILL FINANCIAL SERVICES
                             INTERNATIONAL, Inc, as Lender

                             By: /s/ Mark Guidinger
                                -----------------------------------
                                     Name: Mark Guidinger
                                     Title: Portfolio Manager

                             By: /s/ Paula M. Buetow
                                -----------------------------------
                                     Name: Paula M. Buetow
                                     Title: Operations Manager

                             DEUTSCHE BANK TRUST COMPANY AMERICAS,
                             as Lender
                             By: DB Services New Jersey, Inc.

                             By: /s/ Joseph Cusmai
                                -----------------------------------
                                     Name: Joseph Cusmai
                                     Title: Vice President

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                             WACHOVIA INVESTORS, INC.,
                             as resigning Administrative Agent, resigning
                             Collateral Agent and Lender

                             By: /s/ Ron Ferguson
                                -----------------------------------
                                     Name: Ron Ferguson
                                     Title: Managing Director

                             WACHOVIA BANK. N.A., as Lender

                             BY: /s/ Joel Thomas
                                -----------------------------------
                                     Name: Joel Thomas
                                     Title: Director

                             GENERAL ELECTRIC CAPITAL CORPORATION,
                             as successor Administrative Agent, successor
                             Collateral Agent, Syndication Agent and Lender

                             BY: /s/ Molly S. Fergusson
                                -----------------------------------
                                     Name: Molly S. Fergusson
                                     Title: Duly Authorized Signatory

                             MORGAN STANLEY SENIOR FUNDING, INC.,
                             as Documentation Agent and Lender

                             By: /s/ Ian Sandler
                                -----------------------------------
                                     Name: Ian Sandler
                                     Title: Vice President

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                                     CONSENT

                                                         Dated as of May 5, 2004

            Each of the undersigned as Grantor and/or Pledgor under the Third
Amended and Restated Security Agreement, dated as of September 13, 2002 (the
"Security Agreement") and/or the Third Amended and Restated Pledge Agreement
(the 'Pledge Agreement"), in each case, in favor of the Administrative Agent,
for its benefit and the benefit of the Lenders parties to the Credit Agreement
referred to in the foregoing Second Amendment, hereby consents to such Second
Amendment and hereby confirms and agrees that (a) notwithstanding the
effectiveness of such Second Amendment, each of the Security Agreement and the
Pledge Agreement is, and shall continue to be, in full force and effect and is
hereby ratified and confirmed in all respects, except that, on and after the
effectiveness of such Second Amendment, each reference in the Security Agreement
and the Pledge Agreement to the "Credit Agreement", "thereunder", "thereof" or
words of like import shall mean and be a reference to the Credit Agreement, as
amended by such Second Amendment, and (b) the Security Documents to which such
Grantor or such Pledgor is a party and all of the Collateral described therein
do, and shall continue to, secure the payment of all of the Secured Obligations
(in each case, as defined therein).

                             CHOICE ONE COMMUNICATIONS INC.
                             CHOICE ONE COMMUNICATIONS OF NEW YORK INC.
                             CHOICE ONE COMMUNICATIONS OF PENNSYLVANIA INC.
                             CHOICE ONE COMMUNICATIONS OF MASSACHUSETTS INC.
                             CHOICE ONE COMMUNICATIONS INTERNATIONAL INC.
                             CHOICE ONE COMMUNICATIONS OF RHODE ISLAND INC.
                             CHOICE ONE COMMUNICATIONS OF CONNECTICUT INC.
                             CHOICE ONE COMMUNICATIONS OF MAINE INC.
                             CHOICE ONE OF NEW HAMPSHIRE INC.
                             CHOICE ONE COMMUNICATIONS OF OHIO INC.
                             CHOICE ONE COMMUNICATIONS OF VERMONT INC.
                             CHOICE ONE ONLINE INC.
                             CHOICE ONE COMMUNICATIONS OF VIRGINIA INC.
                             CHOICE ONE COMMUNICATIONS SERVICES INC.
                             US XCHANGE INC.
                             US XCHANGE OF INDIANA, L.L.C.
                             US XCHANGE OF ILLINOIS, L.L.C.
                             US XCHANGE OF WISCONSIN, L.L.C.
                             US XCHANGE OF MICHIGAN, L.L.C.

                             By: /s/ Ajay Sabherwal
                                -----------------------------------
                                     Name: Ajay Sabherwal
                                     Title: EVP & CFO