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                                                                    EXHIBIT 10.4

                    SECURED CONTINUING CORPORATE GUARANTY

         FOR VALUE RECEIVED, and in consideration of any loan or other financial
accommodation heretofore or hereafter at any time made or granted to DIGITAL
NETWORKS CORPORATION (formerly known as "Agoura Hills Corporation") and
MCSi-TEXAS, INC. (formerly known as "MCSi-IG-PV, Inc.") (the "Borrower"), by
ZENGINE, INC. ("Lender"), the undersigned, MCSi-CALIFORNIA, INC. (formerly known
as "West Lake Acquisition Corporation") ("Guarantor"), hereby agrees as follows:

         1. GUARANTY OF OBLIGATIONS. Guarantor unconditionally, absolutely and
irrevocably guarantees the full and prompt payment and performance when due,
whether by acceleration or otherwise, and at all times thereafter, of all
obligations of Borrower to Lender, howsoever created, arising or evidenced,
whether direct or indirect, absolute or contingent, or now or hereafter existing
or due or to become due, including, without limitation, under or in connection
with that certain Loan Agreement of even date, among Guarantor, Borrower and
Lender (the "Loan Agreement") and each of the documents, instruments and
agreements executed and delivered in connection therewith, as each may be
modified, amended, supplemented or replaced from time to time (all such
obligations are herein referred to collectively as the "Liabilities", and all
documents evidencing or securing any of the Liabilities are herein referred to,
collectively, as the "Loan Documents"). This Secured Continuing Corporate
Guaranty (this "Continuing Guaranty") is a guaranty of payment and performance
when due and not of collection.

         In the event of any default by Borrower in making payment of, or
default by Borrower in performance of, any of the Liabilities, Guarantor agrees
on demand by Lender to pay and perform all of the Liabilities as are then or
thereafter become due and owing or are to be performed under the terms of the
Loan Documents. Guarantor further agrees to pay all expenses (including
reasonable attorneys' fees and expenses) paid or incurred by Lender in
endeavoring to collect the Liabilities, or any part thereof, and in enforcing
this Continuing Guaranty.

         2. SECURITY FOR CONTINUING GUARANTY. This Continuing Guaranty is
secured by the collateral pledged by Guarantor and Borrower pursuant to the Loan
Agreement and the other Loan Documents.

         3. CONTINUING NATURE OF GUARANTY AND LIABILITIES. This Continuing
Guaranty shall be continuing and shall not be discharged, impaired or affected
by:

                  (a) the insolvency of Borrower;

                  (b) the power or authority or lack thereof of Borrower to
incur the Liabilities;

                  (c) the validity or invalidity of any of the Loan Documents or
the documents securing the same;



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                  (d) the existence or non-existence of Borrower as a legal
entity;

                  (e) any transfer by Borrower of all or any part of any
collateral in which Lender has been granted a lien or security interest pursuant
to the Loan Documents;

                  (f) any statute of limitations affecting the liability of
Guarantor under this Continuing Guaranty or the Loan Documents or the ability of
Lender to enforce this Continuing Guaranty or any provision of the Loan
Documents; or

                  (g) any right of offset, counterclaim or defense of Guarantor,
including, without limitation, those which have been waived by Guarantor
pursuant to Paragraph 7 hereof.

         4. INSOLVENCY OF BORROWER OR GUARANTOR. Without limiting the generality
of any other provision hereof, Guarantor agrees that, in the event of the
dissolution or insolvency of Borrower or Guarantor or the inability of Borrower
or Guarantor to pay their respective debts as they mature, or an assignment by
Borrower or Guarantor for the benefit of creditors, or the institution of any
proceeding by or against Borrower or Guarantor alleging that Borrower or
Guarantor is insolvent or unable to pay their respective debts as they mature,
Guarantor will pay to Lender forthwith the full amount which would be payable
hereunder by Guarantor if all of the Liabilities were then due and payable,
whether or not such event occurs at a time when any of the Liabilities are
otherwise due and payable.

         5. PAYMENT OF THE LIABILITIES. Any amounts received by Lender from
whatever source on account of the Liabilities may be applied by Lender toward
the payment of such of the Liabilities, and in such order of application, in
accordance with the Loan Agreement as if paid by a Borrower, and notwithstanding
any payments made by or for the account of Guarantor pursuant to this Continuing
Guaranty.

Guarantor agrees that, if at any time all or any part of any payment theretofore
applied by Lender to any of the Liabilities is or must be rescinded or returned
by Lender for any reason whatsoever (including, without limitation, the
insolvency, bankruptcy or reorganization of Borrower), such Liabilities shall,
for the purposes of this Continuing Guaranty and to the extent that such payment
is or must be rescinded or returned, be deemed to have continued in existence
notwithstanding such application by Lender, and this Continuing Guaranty shall
continue to be effective or be reinstated, as the case may be, as to such
Liabilities, all as though such application by Lender had not been made.

         6. PERMITTED ACTIONS OF LENDER. Lender may from time to time, in its
sole discretion and without notice to Guarantor, take any or all of the
following actions:

                  (a) retain or obtain a security interest in any assets of
Borrower or any third party to secure any of the Liabilities or any obligations
of Guarantor hereunder;


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                  (b) retain or obtain the primary or secondary obligation of
any obligor or obligors, in addition to Guarantor, with respect to any of the
Liabilities;

                  (c) extend or renew for one or more periods (whether or not
longer than the original period), alter or exchange any of the Liabilities;

                  (d) waive, ignore or forbear from taking action or otherwise
exercising any of its default rights or remedies with respect to any default by
Borrower under the Loan Documents;

                  (e) release, waive or compromise any obligation of Guarantor
hereunder or any obligation of any nature of any other obligor primarily or
secondarily obligated with respect to any of the Liabilities;

                  (f) release its security interest in, or surrender, release or
permit any substitution or exchange for, all or any part of any collateral now
or hereafter securing any of the Liabilities or any obligation hereunder, or
extend or renew for one or more periods (whether or not longer than the original
period) or release, waive, compromise, alter or exchange any obligations of any
nature of any obligor with respect to any such property; and

                  (g) demand payment or performance of any of the Liabilities
from Guarantor at any time or from time to time, whether or not Lender shall
have exercised any of its rights or remedies with respect to any property
securing any of the Liabilities or any obligation hereunder or proceeded against
any other obligor primarily or secondarily liable for payment or performance of
any of the Liabilities.

         7. SPECIFIC WAIVERS. Without limiting the generality of any other
provision of this Continuing Guaranty, Guarantor hereby expressly waives:

                  (a) notice of the acceptance by Lender of this Continuing
Guaranty;

                  (b) notice of the existence, creation, payment, nonpayment,
performance or nonperformance of all or any of the Liabilities;

                  (c) presentment, demand, notice of dishonor, protest, notice
of protest and all other notices whatsoever with respect to the payment or
performance of the Liabilities or the amount thereof or any payment or
performance by Guarantor hereunder;

                  (d) all diligence in collection or protection of or
realization upon the Liabilities or any thereof, any obligation hereunder or any
security for or guaranty of any of the foregoing;

                  (e) any right to direct or affect the manner or timing of
Lender's enforcement of its rights or remedies;


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                  (f) any and all defenses which would otherwise arise upon the
occurrence of any event or contingency described in Paragraph 1 hereof or upon
the taking of any action by Lender permitted hereunder;

                  (g) any defense, right of set-off, claim or counterclaim
whatsoever and any and all other rights, benefits, protections and other
defenses available to Guarantor now or at any time hereafter, including, without
limitation, under California Civil Code Sections 2787 to 2855, inclusive, and
California Code of Civil Procedure Sections 580a, 580b, 580d or 726, and all
successor sections; and

                  (h) all other principles or provisions of law, if any, that
conflict with the terms of this Continuing Guaranty, including, without
limitation, the effect of any circumstances that may or might constitute a legal
or equitable discharge of a guarantor or surety.

         8. IRREVOCABILITY. Guarantor hereby further waives all rights to revoke
this Continuing Guaranty at any time, and all rights to revoke any agreement
executed by Guarantor at any time to secure the payment and performance of
Guarantor's obligations under this Continuing Guaranty.

         9. STATUTORY WAIVER OF RIGHTS AND DEFENSES REGARDING ELECTION OF
REMEDIES. Guarantor waives all rights and defenses arising out of an election of
remedies by Lender, even though that election of remedies, such as a nonjudicial
foreclosure with respect to security for a guaranteed obligation, has destroyed
Guarantor's rights of subrogation and reimbursement against Borrower by the
operation of any applicable law, including without limitation Section 580d of
the California Code of Civil Procedure, or otherwise.

         10. SUBORDINATION. Except as otherwise permitted in the Loan Agreement,
(i) Guarantor hereby subordinates any and all indebtedness of Borrower to
Guarantor to the full and prompt payment and performance of all of the
Liabilities, and (ii) Guarantor agrees that Lender shall be entitled to receive
payment of all Liabilities prior to Guarantor's receipt of payment of any amount
of any indebtedness of Borrower to Guarantor. Any payments on such indebtedness
to Guarantor, if made in violation of this paragraph, if Lender so requests,
shall be collected, enforced and received by Guarantor, in trust, as trustee for
Lender and shall be paid over to Lender on account of the Liabilities, but
without reducing or affecting in any manner the liability of Guarantor under the
other provisions of this Guaranty.

         11. SUBROGATION. Guarantor will not exercise any rights which it may
acquire by way of subrogation under this Continuing Guaranty, by any payment
hereunder or otherwise, until all of the Liabilities have been paid in full, in
cash. If any amount shall be paid to Guarantor on account of such subrogation
rights at any other time, such amount shall be held


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in trust for the benefit of Lender and shall be forthwith paid to Lender to be
credited and applied to the Liabilities, whether matured or unmatured, in
accordance with the Loan Agreement as if paid by a Borrower.

         12. ASSIGNMENT OF LENDER'S RIGHTS. Lender may, from time to time,
without notice to Guarantor, assign or transfer any or all of the Liabilities or
any interest therein (subject to the limitations on such assignment or transfer
set forth in Section 3.8 of the Loan Agreement) and, notwithstanding any such
assignment or transfer of the Liabilities or any subsequent assignment or
transfer thereof, the Liabilities shall be and remain the Liabilities for the
purpose of this Continuing Guaranty. Each and every immediate and successive
assignee or transferee of any of the Liabilities or of any interest therein
shall, to the extent of such party's interest in the Liabilities, be entitled to
the benefits of this Continuing Guaranty to the same extent as if such assignee
or transferee were Lender; PROVIDED, HOWEVER, that unless Lender shall otherwise
consent in writing, Lender shall have an unimpaired right, prior and superior to
that of any such assignee or transferee, to enforce this Continuing Guaranty for
its own benefit as to those of the Liabilities which Lender has not assigned or
transferred.

         13. INDULGENCES NOT WAIVERS. No delay in the exercise of any right or
remedy shall operate as a waiver thereof, and no single or partial exercise by
Lender of any right or remedy shall preclude other or further exercise thereof
or the exercise of any other right or remedy; nor shall any modification or
waiver of any of the provisions of this Continuing Guaranty be binding upon
Lender, except as expressly set forth in a writing duly signed and delivered by
Lender. No action of Lender permitted hereunder shall in any way affect or
impair the rights of Lender or the obligations of Guarantor under this
Continuing Guaranty.

         14. FINANCIAL CONDITION OF BORROWER. Guarantor represents and warrants
that it is fully aware of the financial condition of Borrower, and Guarantor
delivers this Continuing Guaranty based solely upon its own independent
investigation of Borrower's financial condition and in no part upon any
representation or statement of Lender with respect thereto. Guarantor further
represents and warrants that it is in a position to and hereby does assume full
responsibility for obtaining such additional information concerning Borrower's
financial condition as Guarantor may deem material to its obligations hereunder,
and Guarantor is not relying upon, nor expecting Lender to furnish it any
information in Lender's possession concerning Borrower's financial condition or
concerning any circumstances bearing on the existence or creation, or the risk
of nonpayment or nonperformance of the Liabilities.

         Guarantor hereby waives any duty on the part of Lender to disclose to
Guarantor any facts it may now or hereafter know about Borrower, regardless of
whether Lender has reason to believe that any such facts materially increase the
risk beyond that which Guarantor intends to assume or has reason to believe that
such facts are unknown to Guarantor.


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         Guarantor hereby knowingly accepts the full range of risk encompassed
within a contract of "Continuing Guaranty" which includes, without limitation,
the possibility that Borrower will contract for additional indebtedness for
which Guarantor may be liable hereunder after Borrower's financial condition or
ability to pay its lawful debts when they fall due has deteriorated.

         15. REPRESENTATIONS AND WARRANTIES. Guarantor represents and warrants
to Lender that, except as set forth in the Loan Agreement, each of the following
statements is accurate and complete as of the date of this Continuing Guaranty:

                  (a) this Continuing Guaranty has been duly executed and
delivered by Guarantor and constitutes a legal, valid and binding obligation of
Guarantor, enforceable against Guarantor in accordance with its terms, except as
limited by bankruptcy, insolvency or other laws of general application relating
to or affecting the enforcement of creditors' rights generally;

                  (b) the execution, delivery and performance of this Continuing
Guaranty do not (i) violate any provisions of law or any order of any court or
other agency of government (each, a "Requirement of Law"), (ii) contravene any
provision of any material contract or agreement to which Guarantor is a party or
by which Guarantor or Guarantor's assets are bound (each, a "Contractual
Obligation"), or (iii) result in the creation or imposition of any lien, charge
or encumbrance of any nature upon any property, asset or revenue of Guarantor
except as set forth herein and in the Loan Agreement;

                  (c) all consents, approvals, orders and authorizations of, and
registrations, declarations and filings with, any governmental agency or
authority or other person or entity (including, without limitation, the
shareholders or partners of any entity), if any, which are required to be
obtained in connection with the execution and delivery of this Continuing
Guaranty or the performance of Guarantor's obligations hereunder have been
obtained, and each is in full force and effect;

                  (d) each of the representations and warranties of the
Guarantor in the Loan Agreement is accurate and complete on and as of the date
hereof.

         16. GUARANTOR FINANCIAL INFORMATION. Guarantor will provide Lender in
writing such financial and other information with respect to Guarantor's assets
and liabilities as Lender shall reasonably request from time to time, in form
satisfactory to Lender.

         17. BINDING UPON SUCCESSORS. This Continuing Guaranty shall be binding
upon Guarantor and Guarantor's successors and assigns and shall inure to the
benefit of Lender and its successors and assigns.


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         All references herein to Borrower shall be deemed to include its
successors and assigns, and all references herein to Guarantor shall be deemed
to include Guarantor and Guarantor's successors and assigns.

         In addition and notwithstanding anything to the contrary contained in
this Continuing Guaranty or in any other document, instrument or agreement
between or among any of Lender, Borrower, Guarantor or any third party, the
obligations of Guarantor with respect to the Liabilities shall be joint and
several with any other person or entity that now or hereafter executes a
guaranty of any of the Liabilities separate from this Continuing Guaranty.

         18. NOTICES. All notices required or permitted to be given hereunder
shall be given and deemed received as provided in the Loan Agreement.

         19. GOVERNING LAW; ADDITIONAL WAIVERS. This Continuing Guaranty has
been delivered and shall be governed by and construed in accordance with the
internal laws (as opposed to the conflicts of law provisions) of the State of
California.

         GUARANTOR HEREBY

                  (i) WAIVES ANY RIGHT TO A TRIAL BY JURY IN ANY ACTION TO
         ENFORCE OR DEFEND ANY MATTER ARISING FROM OR RELATED TO THIS CONTINUING
         GUARANTY, AND ACKNOWLEDGES THAT LENDER ALSO WAIVES SUCH RIGHT;

                  (ii) IRREVOCABLY SUBMITS TO THE JURISDICTION OF ANY STATE OR
         FEDERAL COURT LOCATED IN ALAMEDA COUNTY, CALIFORNIA, OVER ANY ACTION OR
         PROCEEDING TO ENFORCE OR DEFEND ANY MATTER ARISING FROM OR RELATED TO
         THIS CONTINUING GUARANTY;

                  (iii) IRREVOCABLY WAIVES, TO THE FULLEST EXTENT GUARANTOR MAY
         EFFECTIVELY DO SO, THE DEFENSE OF AN INCONVENIENT FORUM TO THE
         MAINTENANCE OF ANY SUCH ACTION OR PROCEEDING;

                  (iv) agrees that a final judgment in any such action or
         proceeding shall be conclusive and may be enforced in any other
         jurisdictions by suit on the judgment or in any other manner provided
         by law; and

                  (v) agrees not to institute any legal action or proceeding
         against Lender or any of Lender's directors, officers, employees,
         agents or property concerning any matter arising out of or relating to
         this Continuing Guaranty in any court other than one located in Alameda
         County, California.


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                  (vi) Nothing herein shall affect or impair Lender's right to
         serve legal process in any manner permitted by law or Lender's right to
         bring any action or proceeding against Guarantor or its property in the
         courts of any other jurisdiction. Wherever possible each provision of
         this Continuing Guaranty shall be interpreted as to be effective and
         valid under applicable law, but if any provision of this Continuing
         Guaranty shall be prohibited by or invalid under such law, such
         provision shall be ineffective only to the extent of such prohibition
         or invalidity, without invalidating the remainder of such provision or
         the remaining provisions of this Continuing Guaranty.

         20. ENTIRE AGREEMENT. This Continuing Guaranty, along with the Loan
Documents, contains the complete understanding of the parties hereto with
respect to the subject matter herein. Guarantor acknowledges that Guarantor is
not relying upon any statements or representations of Lender not contained in
this Continuing Guaranty and that such statements or representations, if any,
are of no force or effect and are fully superseded by this Continuing Guaranty.
This Continuing Guaranty may only be modified by a writing executed by Guarantor
and Lender.



                     [THIS SPACE INTENTIONALLY LEFT BLANK.]


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         IN WITNESS WHEREOF, Guarantor has executed this Continuing Guaranty as
of the 29th day of December, 2000, on this January 29, 2001.

                                     "GUARANTOR"

                                     MCSi-CALIFORNIA, INC. (formerly known as
                                     "West Lake Acquisition Corporation")

                                     By:   /s/ IRA H. STANLEY
                                       -----------------------------------------
                                     Name: Ira H. Stanley
                                     Title: Vice President