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                          Lock Up and Voting Agreement

This is a Lock Up and Voting Agreement dated February 28, 2000, by and between
Register.com, Inc., a Delaware corporation ("Register"), and Staples, Inc., a
Delaware corporation ("Staples").

                                   Background

Staples holds 2,041,666 shares of Register's Common Stock, $0.0001 par value per
share ("Common Stock"), 120,659 shares of Register's Series A Convertible
Preferred Stock, $0.0001 par value per share ("Series A Preferred"), a warrant
to purchase 700,000 shares of Common Stock (the "Common Warrant") and additional
warrants to purchase 24,136 shares of Common Stock (the "Series A Warrants"). In
addition, Staples has agreed to purchase, from another Register shareholder, a
warrant to acquire an additional 918,239 shares of Common Stock upon Register's
initial public offering (the "Cap Ex Warrant"). Further, Staples has agreed to
purchase, from two other Register shareholders (i) 75,000 additional shares of
Common Stock of Register (the "Forman Stock"), and (ii) 75,000 additional shares
of Common Stock of Register (the "Palisade Stock"), upon Register's initial
public offering. The share numbers above give effect to Register's recent 3.5
for 1 stock split, effected as a stock dividend.

                                    Agreement

In consideration of the mutual promises and covenants contained herein and for
other good and valuable consideration, the receipt and sufficiency of which are
hereby acknowledged, the undersigned hereby agree as follows:

1.   Restriction on Transfer. Without the prior written consent of Register,
     which shall not unreasonably be withheld, Staples shall not at any time
     before the Transfer Date (as defined below) sell, transfer or otherwise
     dispose of any shares of Common Stock or Series A Preferred, the Common
     Warrant, the Series A Warrants, the Cap Ex Warrant, the Forman Stock or the
     Palisade Stock, or the shares underlying any of the foregoing, or any other
     securities issued by Register now held or hereafter acquired by Staples.
     For purposes of this Agreement, the term "Transfer Date" shall mean the
     first anniversary of the effective date for Register's registration
     statement for its initial public offering (the "Registration Statement").
     This provision and the restrictions on transfer contained herein shall
     terminate in the event that such effective date does not occur on or before
     May 31, 2000. Notwithstanding the foregoing, Staples may transfer any or
     all of such securities to entities controlling, controlled by or under
     common control with Staples; provided, however, that in any such case it
     shall be a condition to the transfer that the transferee execute an
     agreement stating that the transferee is receiving and holding the
     securities subject to the provisions of this Agreement, and there shall be
     no further transfer of such securities except in accordance with this
     Agreement.

2.   Voting. So long as Staples holds more than 5% of the voting power
     represented by Register's outstanding shares of Common Stock, Series A
     Preferred or other voting securities, Staples shall not vote against any
     matter put before the shareholders of Register for approval where holders
     of at least a majority of the voting securities of Register, excluding all
     shares held by Staples, entitled to vote thereon, and that are present or
     represented by proxy, vote in favor of the proposal (or in the case of a
     written consent of the shareholders without a meeting, where holders of a
     majority of the voting securities of Register, excluding all shares held by
     Staples, entitled to express consent with respect thereto, consent to such
     proposal), except for any action or proposal that would adversely affect
     Staples' rights, preferences or privileges as a shareholder in a manner
     different from those of other shareholders.
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3.   Registration Rights. The Forman Stock and the Palisade Stock shall
     constitute Registrable Securities (as defined in the Rights Agreement) for
     purposes of the Registration Rights Agreement dated June 30, 1999, by and
     among Register, Staples and the other investors party thereto (the "Rights
     Agreement"), and Staples shall have all rights under that agreement with
     respect to such shares as if they had been held by Staples and subject to
     the agreement from the date thereof.

4.   Other. This Agreement shall be governed by the laws of the State of New
     York. This Agreement shall not be amended except with the prior written
     consent of the parties hereto. This Agreement constitutes the full and
     entire understanding and agreement of the parties with regard to the
     subject hereof. This Agreement may be executed in counterparts.

In witness whereof, the parties have executed this Agreement as of the date
first set forth above.


REGISTER.COM, INC.                                           STAPLES, INC.

By: /s/ Jack Levy                              By: /s/ Jack VanWoerkom
    ------------------------                       -----------------------------

Name: Jack Levy                                Name: Jack VanWoerkom
      ----------------------                         ---------------------------
Title: General Counsel and                     Title: Senior Vice President and
         Secretary                                      General Counsel