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                          Lock Up and Voting Agreement

This is a Lock Up and Voting Agreement dated February 2, 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 "Additional Warrant"). 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, receipt and sufficiency of which is
hereby acknowledged, the undersigned 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 or the Additional Warrant 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.
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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.

3.   Registration Rights. The shares of Common Stock which Staples may acquire
     upon exercise of the Additional Warrant 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 other investors (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.


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/ Thomas Stemberg
    -----------------------                            -----------------
Name: Jack Levy                                 Name:  Thomas Stemberg
Title: General Counsel and Secretary            Title: CEO