<PAGE>

                                                                   Exhibit 10.01


                       FOURTH AMENDMENT AND RESTATEMENT OF
                          CERTAIN OPERATIVE AGREEMENTS

                         Dated as of September 26, 2001

                                      among

                      VERITAS SOFTWARE GLOBAL CORPORATION,
                  as the Construction Agent and as the Lessee,

          THE VARIOUS PARTIES TO THE PARTICIPATION AGREEMENT AND OTHER
                    OPERATIVE AGREEMENTS FROM TIME TO TIME,
                               as the Guarantors,

                WELLS FARGO BANK NORTHWEST, NATIONAL ASSOCIATION,
    not individually, except as expressly stated in the Operative Agreements,
           but solely as the Owner Trustee under the VS Trust 1999-1,

                THE VARIOUS BANKS AND OTHER LENDING INSTITUTIONS
           WHICH ARE PARTIES TO THE PARTICIPATION AGREEMENT AND OTHER
                    OPERATIVE AGREEMENTS FROM TIME TO TIME,
                                 as the Holders,

                THE VARIOUS BANKS AND OTHER LENDING INSTITUTIONS
           WHICH ARE PARTIES TO THE PARTICIPATION AGREEMENT AND OTHER
                    OPERATIVE AGREEMENTS FROM TIME TO TIME,
                                 as the Lenders,

                                       and

                             BANK OF AMERICA, N.A.,
                       as successor to NATIONSBANK, N.A.,
                      as the Agent for the Secured Parties

--------------------------------------------------------------------------------

                       BANK OF AMERICA, N.A. and KEY BANK,
                                   as Agents,

                                       and

              THE BANK OF NOVA SCOTIA, COMERICA BANK - CALIFORNIA,
   UNION BANK OF CALIFORNIA, N.A., and WELLS FARGO BANK, NATIONAL ASSOCIATION,
                                  as Co-Agents.

--------------------------------------------------------------------------------


<PAGE>


                       FOURTH AMENDMENT AND RESTATEMENT OF
                          CERTAIN OPERATIVE AGREEMENTS

        This FOURTH AMENDMENT AND RESTATEMENT OF CERTAIN OPERATIVE AGREEMENTS
(this "Amendment") dated as of September 26, 2001, is by and among VERITAS
SOFTWARE GLOBAL CORPORATION, a Delaware corporation (the "Lessee" or the
"Construction Agent"); the various parties listed on the signature pages hereto
as guarantors (subject to the definition of Guarantors in Appendix A to the
Participation Agreement referenced below, individually a "Guarantor" and
collectively, the "Guarantors"); WELLS FARGO BANK NORTHWEST, NATIONAL
ASSOCIATION (as successor to First Security Bank, National Association), a
national banking association, not individually but solely as the Owner Trustee
under the VS Trust 1999-1 (the "Owner Trustee" or the "Lessor"); the various
banks and other lending institutions listed on the signature pages hereto
(subject to the definition of Lenders in Appendix A to the Participation
Agreement referenced below, individually, a "Lender" and collectively, the
"Lenders"); BANK OF AMERICA, N.A., a national banking association, which is the
successor to NationsBank, N.A., as the agent for the Lenders and respecting the
Security Documents, as the agent for the Lenders and the Holders, to the extent
of their interests (in such capacity, the "Agent"); and the various banks and
other lending institutions listed on the signature pages hereto as holders of
certificates issued with respect to the VS Trust 1999-1 (subject to the
definition of Holders in Appendix A to the Participation Agreement referenced
below, individually, a "Holder" and collectively, the "Holders"). Capitalized
terms used in this Amendment but not otherwise defined herein shall have the
meanings set forth in Appendix A to the Participation Agreement (hereinafter
defined).

                               W I T N E S S E T H

        WHEREAS, the parties to this Amendment are parties to that certain
Participation Agreement dated as of April 23, 1999 (the "Participation
Agreement"), and certain of the parties to this Amendment are parties to the
other Operative Agreements relating to a $139.4 million tax retention operating
lease facility (the "Facility") that has been established in favor of the
Lessee;

        WHEREAS, the Lessee has requested certain amendments and modifications
to certain of the covenants set forth in the Participation Agreement;

        WHEREAS, the Financing Parties have agreed to the requested amendments
and modifications on the terms and conditions set forth herein;

        NOW, THEREFORE, IN CONSIDERATION of the premises and other good and
valuable consideration, the receipt and sufficiency of which is hereby
acknowledged, the parties agree as follows:


<PAGE>


                             PARTICIPATION AGREEMENT

        1. Clause (iv) of Section 8.3A(a) of the Participation Agreement is
amended in its entirety to read as follows:

                (iv) [Intentionally Left Blank].

        2. Clause (v) of Section 8.3A(a) of the Participation Agreement is
amended in its entirety to read as follows:

                (v) Accountant's Certificate; Other Agreements, Etc. Within 120
        days after the close of each fiscal year of the Lessee, a certificate of
        the accountants conducting the annual audit specifying the nature and
        extent of any Default or Event of Default that they have become aware of
        in their course of review (if the accountants are not aware of any
        Default or Event of Default, no such certificate is required).

        3. Clause (vi) of Section 8.3A(a) of the Participation Agreement is
amended in its entirety to read as follows:

                (vi) Auditor's Reports. Promptly upon receipt thereof, a copy of
        any other report or "management letter" submitted by independent
        accountants to the Parent or any of its Consolidated Subsidiaries in
        connection with any special audit of the books of such Person.

        4. Clause (x) of Section 8.3A(a) of the Participation Agreement is
amended in its entirety to read as follows:

                (x) Other Information. With reasonable promptness upon any such
        request, such other instruments, agreements, certificates, opinions,
        statements, documents and other information regarding the business,
        operations, properties or financial condition of a Credit Party and any
        of its Consolidated Subsidiaries as the Agent or the Majority Secured
        Parties may from time to time reasonably request.

        5. Section 8.3A(h) of the Participation Agreement is amended in its
entirety to read as follows:

                (h) Financial Covenants.

                        (i) Leverage Ratio. The Leverage Ratio, as of the last
                day of each fiscal quarter of the Lessee, shall be less than or
                equal to:

                                (A) From and including September 30, 2001 to and
                                including June 30, 2002, 2.75 to 1.0;

                                (B) From July 1, 2002 to and including September
                                30, 2003, 2.50 to 1.0; and

                                (C) From October 1, 2003 and thereafter, 2.0 to
                                1.0.


                                       2
<PAGE>

                        (ii) EBITDA. EBITDA, for each period set forth below, as
                shown on the financial statements of Credit Parties and their
                Consolidated Subsidiaries delivered pursuant to Section
                8.3(A)(a)(i), shall not be less than (i) $400,000,000 for the
                twelve month period ending September 30, 2001, (ii) $500,000,000
                for the twelve month period ending December 31, 2001 and March
                31, 2002, (iii) $525,000,000 for the twelve month period ending
                June 30, 2002 and September 30, 2002 and (iv) $600,000,000 for
                the twelve month period ending December 31, 2002 and each March
                31, June 30, September 30 and December 31 thereafter.

                        (iii) Quick Ratio. The Quick Ratio, as of the last day
                of each fiscal quarter of the Lessee, shall be greater than or
                equal to 1.20:1.0.

        6. A new clause (i) is added to Section 8.3A of the Participation
Agreement to read as follows:

           (i) Annual Meeting.

               Within ninety (90) days following the end of each fiscal year of
           the Lessee, the Lessee will hold an annual meeting with the Agent,
           the Lenders and the Holders during which the Lessee will review with
           the Agent, the Lenders and the Holders the business plans and
           financial projections of the Lessee for the then-current fiscal year.

        7. Clause (iii) of Section 8.3B(a) of the Participation Agreement is
amended in its entirety to read as follows:

                (iii) purchase money Indebtedness (including obligations in
        respect of Capital Leases) hereafter incurred by a Credit Party or any
        of its Consolidated Subsidiaries to finance the purchase of fixed assets
        provided that (i) the total of all such Indebtedness for all such
        Persons taken together incurred in any fiscal year of the Lessee shall
        not exceed $80,000,000, (ii) the total of all such Indebtedness for all
        such Persons taken together (including any such Indebtedness referred to
        in subsection (ii) above) shall not exceed $160,000,000 at any one time
        outstanding; (iii) such Indebtedness when incurred shall not exceed the
        purchase price of the asset(s) financed; and (iv) no such Indebtedness
        shall be refinanced for a principal amount in excess of the principal
        balance outstanding thereon at the time of such refinancing;

        8. Clause (iv) of Section 8.3B(a) of the Participation Agreement is
amended in its entirety to read as follows:

                (iv) other unsecured Indebtedness (exclusive of Indebtedness
        permitted under subsection (v) and subsection (vi) of this Section
        8.3B(a)) of the Credit Parties and their Consolidated Subsidiaries in an
        aggregate amount not to exceed the sum of $725,000,000 plus twenty
        percent (20%) of the Tangible Net Worth as of the last day of the
        immediately preceding fiscal quarter on terms and conditions
        satisfactory in form and substance to the Majority Secured Parties;
        provided, however, the amount of Indebtedness permitted under this
        subsection (iv) shall be reduced by an amount equal to the sum of (a)
        the aggregate outstanding Loans, plus (b) the aggregate outstanding
        Holder Advances, plus (c) accrued and unpaid Interest or Holder Yield
        due and owing on such Loans or Holder Advances, plus (d) any other
        amounts due and owing by the Lessee or the Construction Agent to any
        Person under any Operative Agreement, plus (e) the aggregate outstanding
        Loans (as such term is defined in Appendix A to the Roseville
        Participation Agreement) under the Roseville Lease Financing, plus (f)
        the aggregate outstanding


                                       3
<PAGE>

        Holder Advances (as such term is defined in Appendix A to the Roseville
        Participation Agreement) under the Roseville Lease Financing plus (g)
        accrued and unpaid Interest or Holder Yield (in each case, as defined in
        Appendix A to the Roseville Participation Agreement) due and owing on
        such Loans or Holder Advances, plus (h) any other amounts due and owing
        by the Lessee or the Construction Agent to any Person under the
        Roseville Lease Financing, plus (i) any Indebtedness outstanding and all
        other amounts due and owing by any Credit Party under the Milpitas Lease
        Financing, plus (j) any Indebtedness outstanding and all other amounts
        due and owing by any Credit Party under the Revolving Credit Agreement;

        9. In Section 8.3B(a), clauses (vii) and (viii) are renumbered as
clauses (ix) and (x) thereof, and new clauses (vii) and (viii) are added thereto
to read as follows:

                (vii) Indebtedness of a Credit Party and its Consolidated
        Subsidiaries arising from the endorsement of instruments for collection
        in the ordinary course of business (other than any such Indebtedness
        arising under any asset securitization program);

                (viii) Indebtedness of a Credit Party and its Consolidated
        Subsidiaries with respect to surety, appeal, indemnity, performance or
        other similar bonds in the ordinary course of business in an aggregate
        outstanding principal amount not to exceed $50,000,000 at any time;

        10. In Section 8.3B(b) of the Participation Agreement, the "." at the
end thereof is deleted and replaced with the following:

                , and (vi) additional Liens provided that the Indebtedness
        secured thereby is permitted under Section 8.3B(a) and the aggregate
        principal amount of the Indebtedness secured thereby does not exceed an
        amount equal to the sum of $100,000,000 plus ten percent of Tangible Net
        Worth as of the last day of the immediately preceding fiscal quarter.

        11. In Section 8.3B(m) of the Participation Agreement, the "." at the
end thereof is deleted and replaced with the following:

        (any such transaction being a "Sale-Leaseback Transaction"); provided,
        however, that the Credit Parties and their Consolidated Subsidiaries may
        enter into a Sale-Leaseback Transaction to the extent that the aggregate
        amount of the sales proceeds of the properties subject to all
        Sale-Leaseback Transactions does not exceed an amount equal to the sum
        of $100,000,000 plus ten percent of Tangible Net Worth as of the last
        day of the fiscal quarter immediately preceding such Sale-Leaseback
        Transaction.

        12. Clause (vii) of the definition of "Permitted Investments" in
Appendix A to the Participation Agreement is amended to read as follows:

                (vii) Investments in any other Person provided that the
        aggregate outstanding amount of all such Investments shall not exceed an
        amount equal to the sum of $175,000,000 plus ten percent of Tangible Net
        Worth as of the last day of the immediately preceding fiscal quarter.

        13. The definition of "Tangible Net Worth" is added to Appendix A to the
Participation Agreement to read as follows:

                "Tangible Net Worth" means, as of any date, shareholders' equity
        or net worth of the Credit Parties and their Consolidated Subsidiaries
        on a consolidated basis minus goodwill, patents, trade names,
        trademarks, copyrights, franchises, organizational expense, deferred


                                       4
<PAGE>

        expenses and other assets in each case as are shown as "intangible
        assets" on a balance sheet of the Credit Parties and their Consolidated
        Subsidiaries on a consolidated basis, as determined in accordance with
        GAAP.

                                  MISCELLANEOUS

        1. This Amendment shall be effective upon satisfaction of the following
conditions:

        (a) execution and delivery of this Amendment by the parties hereto and
execution and delivery of such other documents, agreements or instruments
reasonably deemed necessary or advisable by the Agent; and

        (b) (i) receipt by the Agent of an officer's certificate of the Lessee
        and the Construction Agent (in form and in substance reasonably
        satisfactory to the Agent) specifying that no Default or Event of
        Default shall have occurred and be continuing, specifying that the
        representations and warranties of Lessee set forth in the Participation
        Agreement are true and correct (except for any such representations and
        warranties which relate solely to an earlier time) and certifying as to
        the incumbency of the officer of Lessee executing this Amendment and

            (ii) receipt by the Agent of an officer's certificate of each Credit
        Party (other than the Lessee and the Construction Agent), such officer's
        certificate to be in form and substance reasonably satisfactory to the
        Agent and certifying as to the incumbency of the officer of such Credit
        Party executing this Amendment;

        (c) receipt by the Agent of legal opinions of counsel to the Credit
Parties relating to this Amendment in form and substance reasonably satisfactory
to the Agent; and

        (d) receipt by the Agent, for the ratable benefit of each Lender and
each Holder, of an amendment fee equal to the product of twelve and one half
basis points (0.125%) multiplied by the sum of the aggregate Commitments of all
Lenders and the aggregate Holder Commitments of all Holders after giving effect
to this Amendment.]

        2. Except as modified hereby, all of the terms and provisions of the
Operative Agreements (including Schedules and Exhibits) shall remain unmodified
and in full force and effect.

        3. The Lessee agrees to pay all reasonable costs and expenses of the
Agent in connection with the preparation, execution and delivery of this
Amendment, including without limitation the reasonable fees and expenses of the
Agent's legal counsel.

        4. This Amendment may be executed in any number of counterparts, each of
which when so executed and delivered shall be deemed an original and it shall
not be necessary in making proof of this Amendment to produce or account for
more than one such counterpart.

        5. This Amendment shall be deemed to be a contract made under, and for
all purposes shall be construed in accordance with the laws of the State of New
York.

         [The remainder of this page has been left blank intentionally.]


                                       5
<PAGE>

        IN WITNESS WHEREOF, each of the parties hereto has caused a counterpart
of this Amendment to be duly executed and delivered as of the date first above
written.

                                        VERITAS SOFTWARE GLOBAL CORPORATION,
                                        as the Construction Agent and as
                                        the Lessee

                                        By:        /s/ KEVIN OLSON
                                           -------------------------------------
                                        Name:      Kevin Olson
                                        Title:     Treasurer

                                        VERITAS SOFTWARE CORPORATION,
                                        as a Guarantor


                                        By:        /s/ KEVIN OLSON
                                           -------------------------------------
                                        Name:      Kevin Olson
                                        Title:     Treasurer

                                        VERITAS SOFTWARE TECHNOLOGY CORPORATION,
                                        as a Guarantor


                                        By:        /s/ KEVIN OLSON
                                           -------------------------------------
                                        Name:      Kevin Olson
                                        Title:     Treasurer

                                        VERITAS SOFTWARE TECHNOLOGY HOLDING
                                        CORPORATION, as a Guarantor


                                        By:        /s/ KEVIN OLSON
                                           -------------------------------------
                                        Name:      Kevin Olson
                                        Title:     Treasurer

                           [signature pages continue]


<PAGE>


                                        VERITAS OPERATING CORPORATION,
                                        as a Guarantor

                                        By:        /s/ KEVIN OLSON
                                           -------------------------------------
                                        Name:      Kevin Olson
                                        Title:     Treasurer


<PAGE>


                                        WELLS FARGO BANK NORTHWEST, NATIONAL
                                        ASSOCIATION (as successor to First
                                        Security Bank, National Association),
                                        not individually, but solely as the
                                        Owner Trustee under the VS Trust 1999-1

                                        By:        /s/ VAL T. ORTON
                                           -------------------------------------
                                        Name: Val T. Orton
                                        Title: Vice President


<PAGE>


                                        BANK OF AMERICA, N.A. (which is the
                                        successor to NationsBank, N.A.),
                                        as a Holder, as a Lender and as the
                                        Agent


                                        By: /s/ JOUNI KORHONEN
                                           -------------------------------------
                                        Name: Jouni Korhonen
                                        Title: Managing Director


<PAGE>


                                        COMERICA BANK -- CALIFORNIA,
                                        as a Holder and as a Lender


                                        By:        /s/ ROBERT E. WAYS
                                           -------------------------------------
                                        Name:  Robert E. Ways
                                        Title: Assistant Vice President


<PAGE>


                                        KEYBANK NATIONAL ASSOCIATION,
                                        as a Holder and as a Lender


                                        By:        /s/ JULIEN MICHAELS
                                           -------------------------------------
                                        Name: Julien Michaels
                                        Title: Vice President


<PAGE>


                                        FLEET NATIONAL BANK,
                                        as a Lender

                                        By:        /s/ WILLIAM S. ROWE
                                           -------------------------------------
                                        Name:   William S. Rowe
                                        Title:  Vice President


<PAGE>


                                        THE BANK OF NOVA SCOTIA, as a Lender


                                        By:        /s/ LIZ HANSON
                                           -------------------------------------
                                        Name:      Liz Hanson
                                        Title:     Director


<PAGE>


                                        THE FUJI BANK, LIMITED, as a Lender


                                        By:        /s/ MASAHITO FUKUDA
                                           -------------------------------------
                                        Name: Masahito Fukuda
                                        Title: Senior Vice President


<PAGE>


                                        FBTC LEASING CORP., as a Lender

                                        By:        /s/ VICTOR MORA
                                           -------------------------------------
                                        Name:   Victor Mora
                                        Title:  Vice President


<PAGE>


                                        UNION BANK OF CALIFORNIA, N.A.,
                                        as a Holder and as a Lender


                                        By:        /s/ JAMES B. GOUDY
                                           -------------------------------------
                                        Name:   James B. Goudy
                                        Title:  Vice President


<PAGE>


                                        WELLS FARGO BANK, NATIONAL ASSOCIATION,
                                        as a Holder and as a Lender


                                        By:        /s/ VAL T. ORTON
                                           -------------------------------------
                                        Name:   Val T. Orton
                                        Title:  Vice President


<PAGE>


                                        THE INDUSTRIAL BANK OF JAPAN, LIMITED,
                                        as a Lender



                                        By: /s/ MASAO NAKAGAWA
                                           -------------------------------------
                                        Name:  Masao Nakagawa
                                        Title: Senior Vice President &
                                               Senior Manager


<PAGE>


                                        IBJTC LEASING CORPORATION-BSC,
                                        as a Holder


                                        By:        /s/ TOMOKO AOKI
                                           -------------------------------------
                                        Name:  Tomoko Aoki
                                        Title: Senior Vice President

                              [signature pages end]