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                                                                    EXHIBIT 4.02

                              AMENDMENT NO. ONE TO
                          REGISTRATION RIGHTS AGREEMENT

         This Amendment No. One to Registration Rights Agreement (the
"Amendment") is entered into between Symantec Corporation (the "Company") and
the investors (the "Investors") who hold registration rights under that certain
Registration Rights Agreement dated as of August 31, 1990 (the "Agreement") and
will be effective as of the date (the "Effective Date") that the Company issues
those 7.75% Convertible Subordinated Notes (the "Notes") pursuant to Private
Placement Number: 871503 A#5 Maturity 02/28/2001 (the "Note Offering"). All
capitalized terms not defined hereunder shall have the meanings ascribed to them
under the Agreement.

                                    RECITALS

         A.       On August 31, 1990 the Company and the-Investors entered into
the Agreement granting the Investors certain rights to require the Company to
register their shares of Company Common Stock under the 1933 Act.

         B.       Section 5 of the Agreement provides that the Agreement may be
amended and the observance thereof may be waived with the written consent of the
Company and the holders of two-thirds (2/3) of the combined Registrable
Securities and Registrable Merger Securities then outstanding.

         C.       The Company is making a private placement of up to $25 Million
of Notes, which Notes are convertible (at the option of the holder) into shares
of Company Common Stock (the "Convertible Shares").

         D.       Pursuant to Section 9 of the Note Purchase Agreement between
the Company and the purchasers of the Notes (the "Note Purchase Agreement"), the
Company has agreed to grant such purchasers (the "Purchasers") shelf, demand and
incidental registration rights with respect to the Convertible Shares (the "New
Registration Rights").

         E.       Pursuant to Section 3.1(v) of the Note Purchase Agreement, the
Company is required to represent that no holder of the Company's securities has
any right to require registration of shares of Common Stock because of the
filing of any registration statement covered by the New Registration Rights.

         F.       In order to facilitate the Note Offering, the Company and the
Investors desire to have the Investors waive their rights pursuant to Section 3
of the Agreement to register their Registrable Shares in any registration
statement covered by the New Registration Rights.

         NOW, THEREFORE, in consideration of the above premises and as an
inducement to the Purchasers to enter into the Note Purchase Agreement with the
Company, the parties agree as follows:

         1.       Consent to Purchaser Registration Rights. The Investors
consent to the Company granting to the Purchasers the New Registration Rights.

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         2.       Waiver of Rights. The Investors agree to waive their rights
pursuant to Section 3 of the Agreement to have their Registrable Securities or
Registrable Merger Securities included in any registration statement filed by
the Company and described in

                  (a)      Section 9.1(a) of the Note Purchase Agreement (Shelf
Registration anticipated to be effective from July 31, 1994 through March 31,
1996); or

                  (b)      Section 9.1(b) of the Note Purchase Agreement (Demand
Registration which may occur at any time after February 28, 1995 and before
March 31, 1996).

The Investors understand and agree that the Note Purchase Agreement is still in
negotiation and that the dates set forth above are approximate and may change
and cover longer or different periods of time before the Note Purchase Agreement
is executed.

         3.       Waiver or Subordination of Rights. The Investors agree to
waive or subordinate their rights pursuant to Section 3 of the Agreement to have
their Registrable Securities or Registrable Merger Securities included in any
registration statement filed by the Company and described in Section 9.1(c) of
the Note Purchase Agreement (Incidental Registration) to the extent that such
waiver or subordination is necessary to avoid any conflict with the rights
granted to the Purchasers under Section 9.1(c) of the Note Purchase Agreement.

         4.       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

By:________________________________        By:__________________________________
                                               John Doerr

                                           _____________________________________
                                               Peter Norton

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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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