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                                                                  EXHIBIT 10.29


                       THIRD AMENDMENT TO CREDIT AGREEMENT

         THIS THIRD AMENDMENT TO CREDIT AGREEMENT (the "Amendment"), dated as of
September 30, 1996, is entered into by and between QUARTERDECK CORPORATION (the
"Borrower") and BANK OF AMERICA NATIONAL TRUST AND SAVINGS ASSOCIATION (the
"Bank").

                                    RECITALS

         A. The Borrower and the Bank are parties to a Credit Agreement dated as
of February 14, 1996, as amended by that First Amendment to Credit Agreement
dated as of March 28, 1996, and that Waiver and Second Amendment to Credit
Agreement dated as of August 13, 1996 (as amended, the "Credit Agreement"),
pursuant to which the Bank has extended certain credit facilities to the
Borrower and its Acceptable Subsidiaries.

         B. The Borrower has requested that the Bank agree to certain amendments
of the Credit Agreement.

         C. The Bank is willing to amend the Credit Agreement, subject to the
terms and conditions of this Amendment.

         NOW, THEREFORE, for valuable consideration, the receipt and adequacy of
which are hereby acknowledged, the parties hereto hereby agree as follows:

         1. Defined Terms. Unless otherwise defined herein, capitalized terms
used herein shall have the meanings, if any, assigned to them in the Credit
Agreement.

         2. Amendments to Credit Agreement.

            (a) Subsection 7.01(d) of the Credit Agreement shall be amended and
restated in its entirety to read as follows:

               "(d) indebtedness secured by liens permitted by subsections
            7.02(f), (n), (o), (p) and (q)."

            (b) Section 7.02 of the Credit Agreement shall be amended by
relettering subsection 7.02(q) as 7.02(r) and inserting the following subsection
(q) after the semicolon at the end of subsection (p) thereof:

               "(q) liens on offshore assets (including accounts receivable but
            excluding cash) owned by any offshore Subsidiary, securing
            indebtedness of such offshore Subsidiary not to exceed in aggregate
            principal amount at any one time the Equivalent Amount of
            $5,000,000;"

         3. Representations and Warranties. The Borrower hereby represents and
warrants to the Bank as follows:



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            (a) No Default or Event of Default has occurred and is continuing.

            (b) The execution, delivery and performance by the Borrower of this
Amendment have been duly authorized by all necessary corporate and other action
and do not and will not require any registration with, consent or approval of,
notice to or action by, any Person (including any governmental authority) in
order to be effective and enforceable. The Credit Agreement as amended by this
Amendment constitutes the legal, valid and binding obligations of the Borrower,
enforceable against it in accordance with its respective terms, without defense,
counterclaim or offset.

            (c) All representations and warranties of the Borrower contained in
the Credit Agreement are true and correct as of the date hereof.

            (d) The Borrower is entering into this Amendment on the basis of its
own investigation and for its own reasons, without reliance upon the Bank or any
other Person.

         4. Effective Date. This Amendment will become effective as of the date
first above written (the "Effective Date"), provided that the Bank has received
from the Borrower a duly executed original (or, if elected by the Bank, an
executed facsimile copy) of this Amendment.

         5. Consent of Guarantor. The Borrower, as guarantor with respect to the
obligations of the Acceptable Subsidiaries to the Bank under the Credit
Agreement, as amended by this Amendment, hereby reaffirms and agrees that each
Guaranty to which the Borrower is party, and all other documents and agreements
executed and delivered by the Borrower to the Bank in connection therewith, are
in full force and effect, without defense, offset or counterclaim.

         6. Reservation of Rights. The Borrower acknowledges and agrees that the
execution and delivery by the Bank of this Amendment shall not be deemed to
create a course of dealing or otherwise obligate the Bank to execute similar
consents or amendments under the same or similar circumstances in the future.

         7. Miscellaneous.

            (a) Except as herein expressly amended, all terms, covenants and
provisions of the Credit Agreement are and shall remain in full force and effect
and all references therein to such Credit Agreement shall henceforth refer to
the Credit Agreement as amended by this Amendment. This Amendment shall be
deemed incorporated into, and a part of, the Credit Agreement.

            (b) This Amendment shall be binding upon and inure to the benefit of
the parties hereto and thereto and their 




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respective successors and assigns. No third party beneficiaries are intended in
connection with this Amendment.

            (c) This Amendment shall be governed by and construed in accordance
with the law of the State of California.

            (d) This Amendment may be executed in any number of counterparts,
each of which shall be deemed an original, but all such counterparts together
shall constitute but one and the same instrument. Each of the parties hereto
understands and agrees that this document may be delivered by any party thereto
either in the form of an executed original or an executed original sent by
facsimile transmission to be followed promptly by mailing of a hard copy
original, and that receipt by the Bank of a facsimile transmitted document
purportedly bearing the signature of the Borrower shall bind the Borrower with
the same force and effect as the delivery of a hard copy original. Any failure
by the Bank to receive the hard copy executed original of such document shall
not diminish the binding effect of receipt of the facsimile transmitted executed
original of such document which hard copy ,page was not received by the Bank.

            (e) This Amendment, together with the Credit Agreement, contains the
entire and exclusive agreement of the parties hereto with reference to the
matters discussed herein and therein. This Amendment supersedes all prior drafts
and communications with respect thereto. This Amendment may not be amended
except in accordance with the provisions of Section 9.05 of the Credit
Agreement.

            (f) If any term or provision of this Amendment shall be deemed
prohibited by or invalid under any applicable law, such provision shall be
invalidated without affecting the remaining provisions of this Amendment or the
Credit Agreement, respectively.

            (g) The Borrower covenants to pay to or reimburse the Bank, upon
demand, for all reasonable costs and expenses (including reasonable allocated
costs of in-house counsel) incurred in connection with the development,
preparation, negotiation, execution and delivery of this Amendment.





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            IN WITNESS WHEREOF, the parties hereto have executed and delivered
this Amendment as of the date first above written.


                                       QUARTERDECK CORPORATION


                                       By:/s/ Frank Greico
                                          --------------------------------
                                       Title: Chief Financial Officer


                                       By:
                                       Title:


                                       BANK OF AMERICA NATIONAL TRUST
                                       AND SAVINGS ASSOCIATION


                                       By: /s/ Cecilia Person
                                          --------------------------------
                                       Title: Vice President





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