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                                                                   EXHIBIT 10.45

                                AMENDMENT NO. 2
                                    TO LEASE

        THIS AMENDMENT NO. 2 is made and entered into this 9th day of May,
1996, by and between JOHN ARRILLAGA, Trustee, or his Successor Trustee UTA
dated 7/20/77 (ARRILLAGA FAMILY TRUST) as amended (previously known as the
"John Arrillaga Separate Property Trust"), and RICHARD T. PEERY, Trustee, or
his Successor Trustee UTA dated 7/20/77 (RICHARD T. PEERY SEPARATE PROPERTY
TRUST) as amended, collectively as LANDLORD, and McAfee Associates, a Delaware
corporation, as TENANT.

                                    RECITALS

        A.      WHEREAS, by Lease Agreement dated May 10, 1993 Landlord leased
to Tenant approximately 13,566 +/- square feet of that certain 45,000
more or less square foot building located at 2710 Walsh Avenue, Suite 200,
Santa Clara, California, the details of which are more particularly set forth
in said May 10, 1993 Lease Agreement, and

        B.      WHEREAS, said Lease was amended by the Commencement Letter
dated July 7, 1993 which confirmed (i) the Lease Commencement Date of July 1,
1993, and (ii) the Termination Date of June 30, 1996, and,

        C.      WHEREAS, said Lease was amended by Amendment No. 1 dated
September 27, 1995 which: (i) extended the Term for four (4) years and six (6)
months; (ii) increased the square footage of the Leased Premises by 21,636 +/-
square feet effective January 1, 1996; (iii) increased the square footage of
the Leased Premises by 9,798 plus or minus square feet to 45,000 plus or minus
square feet (100% of the building) effective August 1, 1996; (iv) amended the
Basic Rent schedule and Aggregate Rent accordingly; (v) increased the Security
Deposit due under the Lease; and (vi) added an "Option to Extend" paragraph to
said Lease Agreement, and,

        D.      WHEREAS, it is now the desire of the parties hereto to amend
the Lease by: (i) changing the effective date of the 9,798 +/- square feet of
Increased Premises set forth in Amendment No. 1 from August 1, 1996 to May 10,
1996 and (ii) adjusting the Basic Rent schedule and Aggregate Rent to reflect
the revised commencement date of the additional 9,798 +/- square feet as
hereinafter set forth.

                                   AGREEMENT

        NOW THEREFORE, for valuable consideration, receipt of which is hereby
acknowledged, and in consideration of the hereinafter mutual promises, the
parties hereto do agree as follows:

        1.      INCREASED PREMISES: Effective May 10, 1996, the size of the
Leased Premises will be increased by 9,798 +/- square feet, or from 35,202 plus
or minus square feet to 45,000 +/- square feet of space, representing 100% of
the building. Subject to Lease Paragraph 45 ("Maintenance of the Premises"),
the additional 9,798 +/- square feet of space is leased on an "as-is" basis, in
its present condition and configuration, as set forth in Blue on Exhibit D to
Amendent No. 1, with the entire interior leased Premises shown in Red on
Exhibit D to Amendment No. 1. It is specifically agreed between the parties
that Landlord shall not be required to make, nor be responsible for any cost,
in connection with any repair, restoration, maintenance and/or improvement to
the Increased Premises throughout the Term of this Lease. Landlord makes no
warranty or representation of any kind or nature whatsoever as to the condition
or repair of the Increased Premises, nor as to the use or occupancy which may
be made thereof.

        3.      BASIC RENT SCHEDULE: The monthly Basic Rental shall be adjusted
as follows:

        On May 10, 1996, the sum of SEVEN THOUSAND THREE HUNDRED ONE AND 09/100
DOLLARS ($7,301.09) shall be due, representing the Basic Rental due on the
Increased Premises for the period of May 10, 1996 through May 31, 1996.

        On June 1, 1996, the sum of FORTY FIVE THOUSAND EIGHT HUNDRED NINETY
THREE AND 40/100 DOLLARS ($45,893.40) shall be due, representing the Basic
Rental due for the period of June 1, 1996 through June 30, 1996.

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        On July 1, 1996, the sum of FORTY SEVEN THOUSAND TWO HUNDRED FIFTY AND
NO/100 DOLLARS ($47,250.00) shall be due, and a like sum due on the first day
of each month thereafter, through and including December 1, 1996.

        On January 1, 1997, the sum of FORTY NINE THOUSAND FIVE HUNDRED AND
NO/100 DOLLARS ($49,500.00) shall be due, and a like sum due on the first day
of each month thereafter, through and including December 1, 1997.

        On January 1, 1998, the sum of FIFTY ONE THOUSAND SEVEN HUNDRED FIFTY
AND NO/100 DOLLARS ($51,750.00) shall be due, and a like sum due on the first
day of each month thereafter, through and including December 1, 1998.

        On January 1, 1999, the sum of FIFTY FOUR THOUSAND AND NO/100 DOLLARS
($54,000.00 shall be due, and a like sum due on the first day of each month
thereafter, through and including December 1, 1999.

        On January 1, 2000, the sum of FIFTY SIX THOUSAND TWO HUNDRED FIFTY AND
NO/100 DOLLARS ($56,250.00), shall be due, and a like sum due on the first day
of each month thereafter, through and including December 1, 2000.

        The Aggregate Basic Rent for the Lease shall be increased by $27,876.89
or from $3,367,857.30 to $3,395,734.19.

        EXCEPT AS MODIFIED HEREIN, all other terms, covenants, and conditions
of said May 10, 1993 Lease Agreement shall remain in full force and effect.

        IN WITNESS WHEREOF, Landlord and Tenant have executed this Amendment
No. 2 to Lease as of the day and year last written below.

LANDLORD:                               TENANT:

ARRILLAGA FAMILY TRUST                  MCAFEE ASSOCIATES
                                        a Delaware corporation

By /s/ John Arrillaga                   By /s/ R. J. Schwei
   ---------------------------             -------------------------------
   John Arrillaga, Trustee

Date: 5/22/96                           R. J. Schwei
     -------------------------          ----------------------------------
                                        Print or Type Name
RICHARD T. PEERY SEPARATE     
PROPERTY TRUST                          Title: Secretary
                                              ----------------------------
By /s/ Richard T. Peery
   ---------------------------          Date: 5/15/96
   Richard T. Peery, Trustee                  ----------------------------

Date: 5/23/96
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