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                                                                  EXHIBIT 10.30


                 WAIVER AND FOURTH AMENDMENT TO CREDIT AGREEMENT

         THIS WAIVER AND FOURTH AMENDMENT TO CREDIT AGREEMENT ("Waiver and
Amendment"), dated as of December 17, 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 Bank and the Borrower 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, that Waiver and Second Amendment to Credit Agreement
dated as of August 13, 1996, and that Third Amendment to Credit Agreement dated
as of September 30, 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 reported to the Bank the existence of certain
Events of Default under the Credit Agreement. The Borrower has requested that
the Bank waive certain Events of Default and agree to certain amendments to the
Credit Agreement.

         C. The Bank is willing to waive certain Events of Default under the
Credit Agreement, and to amend the Credit Agreement, subject to the terms and
conditions of this Waiver and 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. Defaults and Waiver.

                  (a) For purposes of this Waiver and Amendment, the "Existing
Defaults" shall mean:

                           (i) the Event of Default existing on this date under
                  Section 8.01(c) of the Credit Agreement as a consequence of a
                  breach of the negative covenant set forth at Section 7.12 of
                  the Credit Agreement solely for the quarter ended September
                  30, 1996 and thereafter through the Effective Date;

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                           (ii) the Event of Default existing on this date under
                  Section 8.01(c) of the Credit Agreement as a consequence of a
                  breach of the negative covenant set forth at Section 7.13 of
                  the Credit Agreement solely for the quarter ended September
                  30, 1996 and thereafter through the Effective Date;

                           (iii) the Event of Default existing on this date
                  under Section 8.01(c) of the Credit Agreement as a consequence
                  of a breach of the negative covenant set forth at Section 7.14
                  of the Credit Agreement solely for the quarter ended September
                  30, 1996 and thereafter through the Effective Date; and

                           (iv) the Event of Default existing on this date under
                  Section 8.01(c) of the Credit Agreement as a consequence of a
                  breach of the negative covenant set forth at Section 7.15 of
                  the Credit Agreement solely for the quarter ended September
                  30, 1996 and thereafter through the Effective Date.

                  (b) Subject to and upon the terms and conditions hereof, the
         Bank hereby waives the Existing Defaults.

                  (c) Nothing contained herein shall be deemed a waiver of (or
         otherwise affect the Bank's ability to enforce) any other default or
         Event of Default, including without limitation (i) any default or Event
         of Default as may now or hereafter exist and arise from or otherwise be
         related to the Existing Defaults (including without limitation any
         cross-default arising under the Credit Agreement by virtue of any
         matters resulting from the Existing Defaults), and (ii) any default or
         Event of Default arising at any time after the Effective Date and which
         arises under the same provisions of the Credit Agreement as those
         implicated by any of the Existing Defaults.

         3.       Amendments to Credit Agreement.

                  (a) Section 1.01 of the Credit Agreement shall be amended at
         the defined term "Borrowing Base" by amending and restating such
         defined term in its entirety as follows:


                           "'Borrowing Base': (i) as of any date of
                  determination thereof before March 31, 1997, an amount equal
                  to 65% of the value of all Eligible Accounts (net of all bad
                  debt reserves, reserves for returns, discounts and marketing
                  funds, or similar reserves applicable thereto) (such net
                  amount, the "Net Eligible Accounts") outstanding at such date,
                  and (ii) as of any 


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                  date of determination thereof on or after March 31, 1997, 
                  75% of the Net Eligible Accounts."

                  (b) Section 1.01 of the Credit Agreement shall be amended by
deleting the defined term "Permitted Acquisition Charges" in its entirety.

                  (c) Section 2.02 of the Credit Agreement shall be amended by
adding the following as new subsection (c) after subsection (b) thereof:

                           "(c) Notwithstanding anything herein to the contrary,
                  no election may be made to have all or portions of Dollar
                  Advances bear interest at the Offshore Rate or to convert any
                  Reference Rate Advance into an Offshore Rate Advance unless,
                  as of the end of the fiscal quarter immediately preceding the
                  date of the requested borrowing or conversion, (i) the ratio
                  on a consolidated basis of (A) the Borrower's total
                  liabilities (which shall include all outstanding Advances (or
                  the Equivalent Amount thereof) and the L/C Outstanding Amount,
                  and exclude the outstanding principal amount of the
                  Subordinated Notes) was less than l.25 times Tangible Net
                  Worth (for purposes of this subsection 2.02(c) only, Tangible
                  Net Worth shall include the outstanding principal amount of
                  the Subordinated Notes) and (ii) on a consolidated basis, the
                  Borrower's (A) unencumbered cash, but including cash subject
                  to encumbrances in favor of the Bank pursuant to the Credit
                  Documents, plus (B) unencumbered short-term marketable
                  securities, less (C) all outstanding Advances (or the
                  Equivalent Amount thereof) and the L/C Outstanding Amount,
                  exceeded $10,000,000. "

                  (d) Section 3.01 shall be amended and restated in its entirety
to read as follows:

                  "3.01 Requests for Credit. Each request for an extension of
         credit shall be made in writing on a form acceptable to the Bank or in
         any other manner acceptable to the Bank. Each request for an extension
         of or renewal of credit (including issuances, amendments or renewals of
         letters of credit) shall include a certification by the chief financial
         officer of the Borrower that (i) the representations and warranties of
         the Borrower contained in this Agreement are and shall be true on and
         as of the date of each extension of credit (except to the extent such
         representations and warranties expressly refer to an earlier date, in
         which case they shall be true and 
        

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                  correct as of such earlier date), (ii) immediately prior to
                  and immediately after giving effect to such extension of
                  credit, no Default or Event of Default exists or shall exist
                  and there shall have occurred no Material Adverse Effect, and
                  (iii) after giving effect to such extension of credit, (x) the
                  aggregate of (A) all Dollar Advances, (B) the Equivalent
                  Amount of all Local Currency Advances and (C) the L/C
                  Outstanding Amount shall not exceed the Credit Limit or the
                  Borrowing Base, and (y) the L/C Outstanding Amount shall not
                  exceed $2,000,000 or the Borrowing Base."

                  (e) Section 6.02(d) of the Credit Agreement shall be amended
and restated in its entirety as follows:

                      "(d) within 25 days after the end of each calendar month 
                  (or, if there exists an Event of Default, more frequently as
                  may be required by the Bank), (i) a Borrowing Base
                  Certificate, (ii) a detailed aging of all accounts receivable
                  outstanding as of such last day in form and substance
                  reasonably requested by the Bank, and (iii) a statement of
                  cash and short-term marketable securities on hand as of such
                  last day in form and substance reasonably requested by the
                  Bank; and"

                  (f) Section 7.12 of the Credit Agreement shall be amended and
restated in its entirety as follows:

                           "7.12 Minimum Cash Balance. The Borrower shall not
                  permit, on a consolidated basis, at any time when the
                  Borrower's consolidated quick ratio as of the last day of the
                  fiscal quarter immediately preceding the time of determination
                  was less than 1.00: 1.00, its balance of unencumbered cash,
                  but including cash subject to encumbrances in favor of the
                  Bank pursuant to the Credit Documents, and unencumbered
                  short-term marketable securities (less all outstanding
                  Advances (or the Equivalent Amount thereof) and the L/C
                  Outstanding Amount) to be less than $3,000,000. For purposes
                  of this Section 7.12, the Borrower's consolidated quick ratio
                  shall mean the ratio of (i) the sum of unencumbered cash,
                  unencumbered short-term cash investments, unencumbered
                  marketable securities not classified as long-term investments
                  and unencumbered accounts receivable (net of any bad debt
                  reserve), but in each case including such item to the extent
                  subject to encumbrances in favor of the Bank pursuant to the
                  Credit Documents, to (ii) current liabilities (which shall
                  include all outstanding 



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                  Advances (or the Equivalent Amount thereof) and the L/C 
                  Outstanding Amount), in each case on a consolidated basis.

                  (g) Section 7.13 of the Credit Agreement shall be amended and
restated in its entirety as follows:

                           "7.13 Total Liabilities to Tangible Net Worth. The
                  Borrower shall not permit as of the last day of any fiscal
                  quarter on a consolidated basis the Borrower's total
                  liabilities (which shall include all outstanding Advances (or
                  the Equivalent Amount thereof) and the L/C Outstanding Amount,
                  and exclude the outstanding principal amount of the
                  Subordinated Notes) to exceed 2.00 times Tangible Net Worth.
                  For purposes of this covenant only, Tangible Net Worth shall
                  include the outstanding principal amount of the Subordinated
                  Notes."

                  (h) Section 7.14 of the Credit Agreement shall be amended and
restated in its entirety as follows:

                           "7.14 Tangible Net Worth. The Borrower shall not
                  permit as of the last day of any fiscal quarter on a
                  consolidated basis its Tangible Net Worth to be less (i) its
                  Tangible Net Worth as of September 30, 1996 plus (ii) the net
                  proceeds from any equity securities issued after September 30,
                  1996, plus (iii) any increase in stockholders' equity
                  resulting from the conversion of debt securities to equity
                  securities after September 30, 1996."

                  (i) Section 7.15 of the Credit Agreement shall be amended and
restated in its entirety as follows:

                           "7.15 Profitability. The Borrower shall not permit as
                  of the last day of any fiscal quarter for the fiscal quarter
                  then ending on a consolidated basis (i) a negative net 
                  operating income, which shall be defined as income before any
                  deduction for interest expense, taxes, or extraordinary items,
                  and without giving effect to any interest or other
                  non-operating income or (ii) a negative net income, which
                  shall be defined as net income after tax (excluding
                  extraordinary items)."

                           (f) Exhibit A to the Credit Agreement shall be
amended and restated in its entirety in the form of Exhibit A attached hereto.

                  (g) Exhibit B to the Credit Agreement shall be amended 


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         and restated in its entirety in the form of Exhibit B attached hereto.

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

                  (a) Other than the Existing Defaults, no Default or Event of
         Default has occurred and is continuing.

                  (b) The execution, delivery and performance by the Borrower of
         this Waiver and 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 Waiver and
         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) Subject to the Existing Defaults, all representations and
         warranties of the Borrower contained in the Credit Agreement are true
         and correct.

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

         5. Effective Date. This Waiver and Amendment will become effective as
of the date first above written (the "Effective Date"), provided that each of
the following conditions precedent are satisfied:

                  (a) The Bank has received from the Borrower a duly executed
         original (or, if elected by the Bank, an executed facsimile copy) of
         this Waiver and Amendment and from Datastorm Technologies, Inc.
         ("Datastorm") a duly executed original (or, if elected by the Bank, an
         executed facsimile copy) of a Pledgor Acknowledgement and Consent in
         the form attached hereto (the "Consent").

                  (b) The Bank has received from the Borrower a copy of a
         resolution passed by the board of directors of such corporation,
         certified by the Secretary or an Assistant Secretary of such
         corporation as being in full force and effect on the date hereof,
         authorizing the execution, delivery and performance of this Waiver and
         Amendment.

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                  (c) All representations and warranties contained herein are
         true and correct as of the Effective Date.

                  (d) The Bank has received from the Borrower the amount of
         $10,000, representing payment in full of a non-refundable amendment fee
         which amount the Borrower hereby covenants to pay to the Bank on
         demand.

         6. 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 Waiver and 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.

         7. Reservation of Rights. The Borrower acknowledges and agrees that
neither the Bank's forbearance in exercising its rights and remedies in
connection with the Existing Defaults, nor the execution and delivery by the
Bank of this Waiver and Amendment, shall be deemed to create a course of dealing
or otherwise obligate the Bank to forbear or execute similar waivers under the
same or similar circumstances in the future.

         8. 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 and in the other Credit
         Documents to such Credit Agreement shall henceforth refer to the Credit
         Agreement as amended by this Waiver and Amendment. This Waiver and
         Amendment shall be deemed incorporated into, and a part of, the Credit
         Agreement.

                  (b) This Waiver and Amendment shall be binding upon and inure
         to the benefit of the parties hereto and thereto and their respective
         successors and assigns. No third party beneficiaries are intended in
         connection with this Waiver and Amendment.

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

                  (d) This Waiver and 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 

         

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         parties hereto and Datastorm, by its execution and delivery of the
         Consent, understands and agrees that this document (and any other
         document required herein) 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 or Datastorm
         shall bind the Borrower or Datastorm, as the case may be, 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 Waiver and 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
         Waiver and Amendment supersedes all prior drafts and communications
         with respect thereto. This Waiver and 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 Waiver and Amendment
         shall be deemed prohibited by or invalid under any applicable law, such
         provision shall be invalidated without affecting the remaining
         provisions of this Waiver and 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 Waiver and Amendment and the administration of the Existing
         Defaults, including without limitation appraisal, audit, search and
         filing fees incurred in connection therewith.

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


                                             QUARTERDECK CORPORATION


                                             By: _______________________________

                                             Title: ____________________________


                                             By: _______________________________

                                             Title: ____________________________


                                             BANK OF AMERICA NATIONAL TRUST
                                             AND SAVINGS ASSOCIATION


                                             By: _______________________________
                                             Title: Vice President


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