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                                    AMENDMENT 2                  Exhibit 10.17.2

THIS AMENDMENT 2 ("Amendment 2") is made and entered into this _____ day of
April, 2002, by and between Williams Communications, LLC, a Delaware limited
liability company ("Williams") and' Universal Access, Inc., a Delaware
corporation ("Customer") having it's principal place of business at Sears Tower,
223 S. Wacker, Suite: 600, Chicago, Illinois 60606.

WHEREAS, Williams and Customer are parties to that certain Master Services
Agreement dated October 1, 2001, contract number 01R1966.00 (the "Agreement") as
amended by Amendment 1, which is dated February 19, 2002 ("Amendment No. 1");
and

WHEREAS, Williams and Customer desire to amend the Agreement;

NOW, THEREFORE in consideration of the foregoing premises and mutual promises
and covenants of the parties hereto, the receipt, and sufficiency of which is
hereby acknowledged, Williams and Customer agree to amend the Agreement as
follows:

1.    Table A.1 of Schedule 1, Private Line Services, shall be deleted in its
      entirety and replaced with the following pricing, which shall only apply
      to new Service Orders placed from the Effective Date of this Amendment and
      shall not apply to Service Orders previously placed by Customer and
      accepted by Williams.

<Table>
<Caption>
                  ------------------------------------------------------
                  Table A.1.  Monthly Recurring Rates
                  ------------------------------------------------------
                  <S>     <C>    <C>    <C>    <C>     <C>
                   Term   DS1    DS3    OC3    OC12    C-48
                  ------------------------------------------------------
                  1 year  ***    ***    ***     ***    ***
                  ------------------------------------------------------
                           Rates are per VGE V&H mile
                  ------------------------------------------------------
</Table>

2.    Table B.1 of Schedule 2, Optical Wave Services, shall be deleted in its
      entirety and replaced with the following pricing, which shall only apply
      to new Service Orders placed from the Effective Date of this Amendment and
      shall not apply to Service Orders previously placed by Customer and
      accepted by Williams.

<Table>
<Caption>
                  ------------------------------------------------------
                  Table B.1         Monthly Recurring Rate
                  ------------------------------------------------------
                  <S>                <C>
                  Term               OC-48
                  ------------------------------------------------------
                  1 year             ***
                  ------------------------------------------------------
                           Rates are per VGE V&H mile
                  ------------------------------------------------------
</Table>

3.    Except as specifically  amended herein, all terms,  conditions and
      provisions contained in the Agreement shall remain unchanged and in full
      force and effect.

     IN WITNESS WHEREOF, the parties have executed this Amendment on the day and
     year set forth below.

UNIVERSAL ACCESS, INC.                   WILLIAMS COMMUNICATIONS, LLC:
/s/ Mark A. Dickey                       /s/ Bryan Dancer
------------------------------           ------------------------------
Signature of Authorized                  Signature of Authorized
Representative                           Representative
Mark A. Dickey                           Bryan Dancer
------------------------------           ------------------------------
Printed Name                             Printed Name
Sr. VP                                   VP of Data Service
------------------------------           ------------------------------
Title                                    Title
4-4-02                                   4-10-02
------------------------------           ------------------------------
Date                                     Date

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