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                     GUARANTY BY CORPORATION 

                                                              Denver, Colorado
                                                               January 3, 1997

          For good and valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, and to induce Norwest Business Credit, Inc., 
a Minnesota corporation (herein, with its participants, successors and 
assigns, called the "Lender"), at its option, at any time or from time to 
time to make loans or extend other accommodations to or for the account of
Service Business Systems, Inc. (herein called the "Borrower") or to engage 
in any other transactions with the Borrower, the undersigned hereby 
absolutely and unconditionally guaranties to the Lender the full and prompt 
payment when due, whether at maturity or earlier by reason of acceleration or
otherwise, of any and all present and future debts, liabilities and
obligations owed by the Borrower to the Lender; and the undersigned 
acknowledges and agrees with the Lender that:

     
           1.       The debts, liabilities and obligations guarantied hereby 
(collectively referred to herein as the "Indebtedness") shall include, but 
shall not be limited to, debts, liabilities and obligations arising out of 
loans, credit transactions, financial accommodations, discounts, purchases of
property or other transactions with the Borrower or for the Borrower's 
account or out of any other transaction or event, owed to the Lender or owed 
to others by reason of participations granted to or interests acquired or 
created for or sold to them by the Lender, in each case whether now existing 
or hereafter arising, whether arising directly in a transaction or event
involving the Lender or acquired by the Lender from another by purchase or 
assignment or as collateral security, whether owed by the Borrower as drawer,
maker, endorser, accommodation party, guarantor, principal, surety or as a 
member of any partnership, syndicate, association or group or in any other 
capacity, whether absolute or contingent, direct or indirect, primary or
secondary, sole, joint, several or joint and several, secured or unsecured, 
due or not due, contractual, tortious or statutory, liquidated or 
unliquidated, arising by agreement or imposed by law or otherwise.

           2.       The undersigned represents and warrants to the Lender 
that (a) the undersigned is a corporation duly organized and existing in good
standing and has full power and authority to make and deliver this guaranty; 
(b) the execution, delivery and performance of this guaranty by the 
undersigned have been duly authorized by all necessary action of its 
directors and shareholders and do not and will not violate the provisions of,
or constitute a default under, any presently applicable law or its articles 
of incorporation or bylaws or any agreement presently binding on it; (c) this
guaranty has been duly executed and delivered by the authorized officers of 
the undersigned and constitutes its lawful, binding and legally enforceable
obligation; and (d) the authorization, execution, delivery and performance of
this guaranty do not require notification to, registration with, or consent 
or approval by, any federal, state or local regulatory body or administrative
agency.

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           3.       No act or thing need occur to establish the liability of 
the undersigned hereunder, and no act or thing, except full payment and 
discharge of all of the Indebtedness, shall in any way exonerate the 
undersigned hereunder or modify, reduce, limit or release the liability of 
the undersigned hereunder.  This is an absolute, unconditional and continuing
guaranty of payment of the Indebtedness and shall continue to be in force and
be binding upon the undersigned, whether or not all of the Indebtedness is 
paid in full, until this guaranty is revoked prospectively as to future 
transactions, by written notice actually received by the Lender, and such 
revocation shall not be effective as to the amount of Indebtedness existing 
or committed for at the time of actual receipt of such notice by the Lender, 
or as to any renewals, extensions, refinancings or refundings thereof.  The 
dissolution or adjudication of bankruptcy of the undersigned shall not revoke
this guaranty, except upon actual receipt of written notice thereof by the 
Lender and only prospectively, as to future transactions, as herein set 
forth.

           4.       The undersigned represents and warrants to the Lender 
that the undersigned has a direct and substantial economic interest in the 
Borrower and expects to derive substantial benefits therefrom and from any 
loans, credit transactions, financial accommodations, discounts, purchases 
of property and other transactions and events resulting in the creation of 
the Indebtedness guarantied hereby, and that this guaranty is given for a 
corporate purpose.  The undersigned agrees to rely exclusively on the right 
to revoke this guaranty prospectively as to future transactions, in 
accordance with paragraph 3, if at any time, in the opinion of the directors 
or officers of the undersigned, the corporate benefits then being received
by the undersigned in connection with this guaranty are not sufficient to 
warrant the continuance of this guaranty as to the future Indebtedness of 
the Borrower.  Accordingly, so long as this guaranty is not revoked 
prospectively in accordance with paragraph 3, the Lender may rely 
conclusively on a continuing warranty, hereby made, that the undersigned 
continues to bebenefitted by this guaranty and the Lender shall have no duty 
to inquire into or confirm the receipt of any such benefits, and this 
guaranty shall be effective and enforceable by the Lender without regard to 
the receipt, nature or value of any such benefits.

           5.       If the undersigned shall be dissolved or shall be or 
become insolvent (however defined), then the Lender shall have the right to 
declare immediately due and payable, and the undersigned will forthwith pay 
to the Lender, the full amount of all of the Indebtedness whether due and 
payable or unmatured.  If the undersigned voluntarily commences or there is
commenced involuntarily against the undersigned a case under the United 
States Bankruptcy Code, the full amount of all Indebtedness, whether due and 
payable or unmatured, shall be immediately due and payable without demand or 
notice thereof.

           6.       The undersigned hereby waives all rights that the 
undersigned may now have or hereafter acquire, whether by subrogation, 
contribution, reimbursement, recourse, exoneration, contract or otherwise, 
to recover from the Borrower or from any property of the Borrower any sums 
paid under this Guaranty.  The undersigned will not exercise or enforce any

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right of contribution to recover any such sums from any person who is a 
co-obligor with the Borrower or a guarantor or surety of the Indebtedness or 
from any property of any such person until all of the Indebtedness shall have
been fully paid and discharged.

           7.       The undersigned will pay or reimburse the Lender for all 
costs, expenses and attorneys' fees paid or incurred by the Lender in 
endeavoring to collect and enforce the Indebtedness and in enforcing this 
guaranty.

           8.       The Lender shall not be obligated by reason of its 
acceptance of this guaranty to engage in any transactions with or for the 
Borrower.  Whether or not any existing relationship between the undersigned 
and the Borrower has been changed or ended and whether or not this guaranty 
has been revoked, the Lender may enter into transactions resulting in the
creation or continuance of the Indebtedness and may otherwise agree, consent 
to or suffer the creation or continuance of any of the Indebtedness, without 
any consent or approval by the undersigned and without any prior or 
subsequent notice to the undersigned.  The liability of the undersigned shall
not be affected or impaired by any of the following acts or things (which the
Lender is expressly authorized to do, omit or suffer from time to time, both 
before and after revocation of this guaranty, without consent or approval by 
or notice to the undersigned): i. any acceptance of collateral security, 
guarantors, accommodation parties or sureties for any or all of the 
Indebtedness; ii. one or more extensions or renewals of the Indebtedness 
(whether or not for longer than the original period) or any modification of 
the interest rates, maturities or other contractual terms applicable to any 
of the Indebtedness or any amendment or modification of any of the terms or 
provisions of any loan agreement or other agreement under which the
Indebtedness or any part thereof arose; iii. any waiver or indulgence granted
to the Borrower, any delay or lack of diligence in the enforcement of the 
Indebtedness or any failure to institute proceedings, file a claim, give any 
required notices or otherwise protect any of the Indebtedness; iv. any full 
or partial release of, compromise or settlement with, or agreement not to 
sue, the Borrower or any guarantor or other person liable in respect of any 
of the Indebtedness; v. any release, surrender, cancellation or other 
discharge of any evidence of the Indebtedness or the acceptance of any 
instrument in renewal or substitution therefor; vi. any failure to obtain
collateral security (including rights of setoff) for the Indebtedness, or to 
see to the proper or sufficient creation and perfection thereof, or to 
establish the priority thereof, or to preserve, protect, insure, care for, 
exercise or enforce any collateral security; or any modification, alteration,
substitution, exchange, surrender, cancellation, termination, release or 
other change, impairment, limitation, loss or discharge of any collateral 
security;  vii. any collection, sale, lease or disposition of, or any other 
foreclosure or enforcement of or realization on, any collateral security; 
viii. any assignment, pledge or other transfer of any of the Indebtedness or 
any evidence thereof; ix. any manner, order or method of application of any 
payments or credits upon the Indebtedness; and x. any election by the Lender 
under Section 1111(b) of the United States Bankruptcy Code.  The undersigned 
waives any and all defenses and discharges available to a surety, guarantor 
or accommodation co-obligor.

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           9.       The undersigned waives any and all defenses, claims, 
setoffs and discharges of the Borrower, or any other obligor, pertaining to 
the Indebtedness, except the defense of discharge by payment in full.  
Without limiting the generality of the foregoing, the undersigned will not 
assert, plead or enforce against the Lender any defense of waiver, release,
discharge or disallowance in bankruptcy, statute of limitations, res 
judicata, statute of frauds, anti-deficiency statute, fraud, incapacity, 
minority, usury, illegality or unenforceability which may be available to 
the Borrower or any other person liable in respect of any of the 
Indebtedness, or any setoff available against the Lender to the Borrower or 
any other such person, whether or not on account of a related transaction.  
The undersigned expressly agrees that the undersigned shall be and remain 
liable for any deficiency remaining after foreclosure of any mortgage or 
security interest securing the Indebtedness, whether or not the liability of 
the Borrower or any other obligor for such deficiency is discharged pursuant 
to statute or judicial decision.  The liability of the undersigned shall not 
be affected or impaired by any voluntary or involuntary liquidation, 
dissolution, sale or other disposition of all or substantially all of the
assets, marshalling of assets and liabilities, receivership, insolvency, 
bankruptcy, assignment for the benefit of creditors, reorganization, 
arrangement, composition or readjustment of, or other similar event or 
proceeding affecting, the Borrower or any of its assets.  The undersigned 
will not assert, plead or enforce against the Lender any claim, defense or 
setoff available to the undersigned against the Borrower.

           10.      The undersigned waives presentment, demand for payment, 
notice of dishonor or nonpayment and protest of any instrument evidencing the
Indebtedness.  The Lender shall not be required first to resort for payment 
of the Indebtedness to the Borrower or other persons, or their properties, or
first to enforce, realize upon or exhaust any collateral security for
the Indebtedness, before enforcing this guaranty.

           11.      If any payment applied by the Lender to the Indebtedness 
is thereafter set aside, recovered, rescinded or required to be returned for 
any reason (including, without limitation, the bankruptcy, insolvency or 
reorganization of the Borrower or any other obligor), the Indebtedness to 
which such payment was applied shall for the purpose of this guaranty be
deemed to have continued in existence, notwithstanding such application, and 
this guaranty shall be enforceable as to such Indebtedness as fully as if 
such application had never been made.

           12.      The undersigned acknowledges and agrees that the Lender 
(a) has not made any representations or warranties with respect to, (b) does 
not assume any responsibility to the undersigned for, and (c) has no duty to 
provide information to the undersigned regarding, the enforceability of any 
of the Indebtedness or the financial condition of the Borrower or any
guarantor.  The undersigned has independently determined the 
creditworthiness of the Borrower and the enforceability of the Indebtedness 
and until the Indebtedness is paid in full will independently and without 
reliance on the Lender continue to make such determinations.

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           13.      The liability of the undersigned under this guaranty is 
in addition to and shall be cumulative with all other liabilities of the 
undersigned to the Lender as guarantor, surety, endorser, accommodation 
co-obligor or otherwise of any of the Indebtedness or obligation of the 
Borrower, without any limitation as to amount, unless the instrument or
agreement evidencing or creating such other liability specifically provides 
to the contrary.

           14.      This guaranty shall be effective upon delivery to the 
Lender, without further act, condition or acceptance by the Lender, shall be 
binding upon the undersigned and the successors and assigns of the 
undersigned and shall inure to the benefit of the Lender and its
participants, successors and assigns.  Any invalidity or unenforceability of 
any provision or application of this guaranty shall not affect other lawful 
provisions and application thereof, and to this end the provisions of this 
guaranty are declared to be severable.  This guaranty may not be
waived, modified, amended, terminated, released or otherwise changed except 
by a writing signed by the undersigned and the Lender.  This guaranty shall 
be governed by and construed in accordance with the substantive laws (other 
than conflict laws) of the State of Colorado.  The undersigned waives notice 
of the Lender's acceptance hereof.  The undersigned irrevocably
i. agrees that any suit, action or other legal proceeding arising out of or 
relating to this guaranty may be brought in a court of record in the State of
Colorado or in the Courts of the United States located in such State, ii. 
consents to the jurisdiction of each such court in any suit, action or
proceeding, iii. waives any objection which it may have to the laying of 
venue of any such suit, action or proceeding in any such courts and any 
claim that any such suit, action or proceeding has been brought in an 
inconvenient forum, and iv. agrees that a final judgment in any such suit,
action or proceeding shall be conclusive and may be enforced in other 
jurisdictions by suit on the judgment or in any other manner provided by law.




















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           15.      THE UNDERSIGNED HEREBY IRREVOCABLY WAIVES ALL
RIGHTS TO TRIAL BY JURY IN ANY ACTION, PROCEEDING OR COUNTERCLAIM
ARISING OUT OF, BASED ON OR PERTAINING TO THIS GUARANTY.

          This guaranty is secured by the "Collateral" as defined in the 
Security Agreement between the undersigned and the Lender dated January 3, 
1997.


          IN WITNESS WHEREOF, this guaranty has been duly executed by the
undersigned the day and year first above written.

(Registrant)                                DATA NATIONAL CORPORATION


BY(Signature)                               /s/Donald V. Warriner
(Name and Title)                            Donald V. Warriner,
                                            President and CEO

                         Address:       11415 West I-70 Frontage Road North
                                        Wheat Ridge, CO  80033
                                        Attn:  Richard S. Simms

STATE OF Colorado   )
                    ) ss.
COUNTY OF Jefferson )

          The foregoing instrument was acknowledged before me this 3rd day of 
January, 1997, by Donald V. Warriner, the President and CEO of Data National
Corporation, a Colorado corporation, on behalf of the corporation.

BY(Signature)                   /s/Thomas J. Moore                           
                                Notary Public








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