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                                                                    EXHIBIT 4.03

                              AMENDMENT NO. TWO TO
                          REGISTRATION RIGHTS AGREEMENT

         This Amendment No. Two to Registration Rights Agreement (the
"AMENDMENT") is entered into between Symantec Corporation ("SYMANTEC") and the
investors (the "INVESTORS") who hold registration rights under that certain
Registration Rights Agreement dated as of August 31, 1990, as amended as of
April 2, 1993 (the "AGREEMENT") and is effective as of the effective date (the
"EFFECTIVE DATE") of the merger ("MERGER") of Symantec Merger Corp., a
wholly-owned subsidiary of Symantec ("SUB") with and into Contact Software
International, Inc. ("CONTACT"). All capitalized terms not defined hereunder
shall have the meanings ascribed to them under the Agreement.

                                    RECITALS

         A.       Sub, Symantec and Contact have entered into an Agreement and
Plan of Reorganization dated as of May 3, 1993 (the "PLAN") providing for the
Merger, whereby Contact will become a wholly-owned subsidiary of Symantec.

         B.       In connection with the Merger, Symantec will grant warrants to
purchase Symantec Common Stock (the "WARRANTS") in exchange for outstanding
warrants to purchase Contact stock, on the terms and conditions set forth in the
Plan.

         C.       Symantec has agreed under the Plan to negotiate in good faith
with respect to entering into a Registration Rights Agreement granting the
holders of the Warrants (the "WARRANTHOLDERS") incidental "piggyback"
registration rights ("NEW PIGGYBACK RIGHTS") with respect to the Symantec Common
Stock issuable upon exercise of the Warrants (the "WARRANT SHARES").

         D.       The Warrantholders have demanded that the New Piggyback Rights
entitle the Warrant Shares to be cut back pro rata with the shares held by the
Investors in the event of an underwriter cut-back for a registration in which
the Warrantholders and the Investors both participate.

         E.       In order to facilitate the Merger, Symantec and the Investors
desire to have the Investors consent to the granting of the New Piggyback Rights
to the Warrantholders and waive their rights pursuant to the Agreement regarding
priority in the event of an underwriter cut-back, vis-a-vis the Warrant Shares.

         NOW, THEREFORE, in consideration-of the above premises, the parties
agree as follows:

         1.       Consent to New Piggyback Rights. The Investors consent to
Symantec granting to the Warrantholders the New Piggyback Rights.

         2.       Underwritten Demand Registration. In the event of an
underwriter cut back in a registration described under Section 3.2(b) of the
Agreement, the Investors consent to the treatment of Warrant Shares requested to
be included in such registration on the same priority as and equivalent to
Registrable Securities.

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         3.       Underwritten Primary Registration. In the event of an
underwriter cut back in a registration described under Section 3.8(b) of the
Agreement, the Investors consent to the treatment of Warrant Shares requested to
be included in such registration on the same priority as and equivalent to
Registrable Securities and Registrable Merger Securities requested to be
included in such registration.

         4.       Underwritten Secondary Registration on Behalf of Holders. In
the event of an underwriter cut back in a registration described under Section
3.8(c) of the Agreement, the Investors consent to the treatment of Warrant
Shares requested to be included in such registration on the same priority as and
equivalent to Registrable Securities requested to be included therein by the
Holders requesting such registration.

         5.       Effect of Amendment. This Amendment may be executed in two or
more counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument. This Amendment shall
become effective when executed by Peter Norton and John Doerr, holders of more
than two-thirds of the currently outstanding Registrable Securities and
Registrable Merger Securities and shall bind all Investors under the Agreement.
Except as otherwise amended herein, the terms of the Agreement shall remain in
full force and effect.

         IN WITNESS WHEREOF, the parties have entered into this Amendment as of
the Effective Date.

SYMANTEC CORPORATION                       INVESTORS:

By:________________________________        _____________________________________
                                           L. John Doerr

                                           _____________________________________
                                           Peter Norton

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