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                                                                   EXHIBIT 10.72

                                    GUARANTY
                               (HAYES CORPORATION)


                                 January 2, 1998


The CIT Group/Credit Finance, Inc.
1211 Avenue of the Americas
21st Floor
New York, New York  10036


            Re:   Hayes Microcomputer Products, Inc., a Georgia corporation
                  ("Borrower")


Gentlemen:

         Reference is made to the financing arrangements between The CIT
Group/Credit Finance, Inc. ("Lender") and Borrower pursuant to which Lender may
extend loans, advances and other financial accommodations to Borrower as set
forth in the Loan and Security Agreement between Borrower and Lender dated
December 21, 1995, as supplemented by that certain Conditions Precedent Rider
dated December 21, 1995 between Lender and Borrower, and as amended by that
certain First Amendment to Loan and Security Agreement dated April 16, 1996
between Lender and Borrower, that certain Second Amendment to Loan and Security
Agreement dated October 15, 1996 between Lender and Borrower, that certain Third
Amendment to Loan and Security Agreement dated as of January 1, 1997, and that
certain Fourth Amendment to Loan and Security Agreement dated on or about the
date hereof, between Lender and Borrower and various other agreements, documents
and instruments now or at any time executed or delivered in connection therewith
or otherwise related thereto, including, but not limited to, this Guaranty (all
of the foregoing, as the same now exist or may hereafter be amended, modified,
supplemented, extended, renewed, restated or replaced, being collectively
referred to herein as the "Financing Agreements").

         Due to the close business and financial relationships between Borrower
and the undersigned ("Guarantor"), in consideration of the benefits which will
accrue to Guarantor, and as an inducement for and in consideration of Lender at
any time providing or extending loans, advances and other financial
accommodations to Borrower, whether pursuant to the Financing Agreements or
otherwise, Guarantor hereby, irrevocably and unconditionally, (a) guarantees,
and agrees to be liable for, the prompt indefeasible and full payment and
performance of all revolving loans, term loans, letters of credit, bankers'
acceptances, merchandise purchase guaranties or other guaranties or indemnities
for Borrower's account and all other obligations, liabilities and indebtedness
of every kind, nature or description owing by Borrower to Lender or Lender's
affiliates, including, without limitation, principal, interest, charges, fees
and expenses, however evidenced, whether as principal, surety, endorser,
guarantor or otherwise, whether arising under any of the Financing Agreements or




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otherwise, whether now existing or hereafter arising, whether arising before,
during or after the initial or any renewal term of the Financing Agreements or
after the commencement of any case with respect to Borrower under the United
States Bankruptcy Code or any similar statute, whether or not such obligations,
liabilities or indebtedness are direct or indirect, absolute or contingent,
joint or several, due or not due, primary or secondary, liquidated or
unliquidated, secured or unsecured, original, renewed or extended, and whether
arising directly or howsoever acquired by Lender including from any other entity
outright, conditionally or as collateral security, by assignment, merger with
any other entity, participations or interests of Lender in the obligations of
Borrower to others, assumption, operation of law, subrogation or otherwise and
(b) agrees to pay to Lender on demand the amount of all expenses (including,
without limitation, attorneys' fees and legal expenses) incurred by Lender in
connection with the preparation, execution, delivery, recording, administration,
collection, liquidation, enforcement and defense of Borrower's obligations,
liabilities and indebtedness as aforesaid to Lender, Lender's rights in any
collateral or under this Guaranty and all other Financing Agreements or in any
way involving claims by or against Lender directly or indirectly arising out of
or related to the relationship between Borrower and Lender, Guarantor and
Lender, or any other Obligor (as hereinafter defined) and Lender, whether such
expenses are incurred before, during or after the initial or any renewal term of
the Financing Agreements or after the commencement of any case with respect to
Borrower, Guarantor or any other Obligor under the United States Bankruptcy Code
or any similar statute (all of which being collectively referred to herein as
the "Guaranteed Obligations").

         GUARANTOR HEREBY EXPRESSLY WAIVES notice of Lender's acceptance of this
Guaranty, the making of loans, advances and extensions of credit or other
financial accommodations to, and the incurring of any expenses by or in respect
of, Borrower, and presentment, demand, protest, notice of protest, notice of
nonpayment or default and all other notices to which Borrower or Guarantor are
or may be entitled. GUARANTOR ALSO WAIVES notice of, and hereby consents to, (i)
any amendment, modification, supplement, renewal, restatement or extensions of
time of payment of or increase or decrease in the amount of any of the
Guaranteed Obligations or to the Financing Agreements and any collateral, and
the guarantee made herein shall apply to the Guaranteed Obligations as so
amended, modified, supplemented, renewed, restated or extended, increased or
decreased, (ii) the taking, exchange, surrender and releasing of any collateral
or guarantees now or at any time held by or available to Lender for the
obligations of Borrower or any other party at any time liable for or in respect
of the Guaranteed Obligations (individually and collectively, the "Obligors"),
(iii) the exercise of, or refraining from the exercise of any rights against
Borrower, Guarantor or any other Obligor or any collateral, and (iv) the
settlement, compromise or release of, or the waiver of any default with respect
to, any Guaranteed Obligations. Guarantor agrees that the amount of the
Guaranteed Obligations shall not be diminished and the liability of Guarantor
hereunder shall not be otherwise impaired or affected by any of the foregoing.
To the fullest extent permitted by applicable law, GUARANTOR HEREBY FURTHER
WAIVES the right to plead any statute of limitations as a defense to performance
of its obligations under, or to Lender's enforcement of, this Guaranty.

         This Guaranty is a guaranty of payment and not of collection. Guarantor
agrees that Lender need not attempt to collect any Guaranteed Obligations from
Borrower or any other Obligor or to realize upon any collateral (and Guarantor
hereby waives the benefit of any statute or other law that



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might otherwise require Lender to institute suit against Borrower or any other
Obligor on Guarantor's request or prior to instituting suit against Guarantor),
but Lender may require Guarantor to make immediate payment of the Guaranteed
Obligations to Lender when due or at any time thereafter. Lender may apply any
amounts received in respect of the Guaranteed Obligations to any of the
Guaranteed Obligations, in whole or in part (including reasonable attorneys'
fees and legal expenses incurred by Lender with respect thereto or otherwise
chargeable to Borrower or Guarantor) and in such order as Lender may elect,
whether or not then due.

         No invalidity, irregularity or unenforceability of all or any part of
the Guaranteed Obligations shall affect, impair or be a defense to this
Guaranty, nor shall any other circumstance which might otherwise constitute a
defense available to, or legal or equitable discharge of Borrower in respect of
any of the Guaranteed Obligations or Guarantor in respect of this Guaranty,
affect, impair or be a defense to this Guaranty. Without limitation of the
foregoing, the liability of Guarantor hereunder shall not be discharged or
impaired in any respect by reason of any failure by Lender to perfect or
continue perfection of any lien or security interest in any collateral for the
Guaranteed Obligations or any delay by Lender in perfecting any such lien or
security interest. As to interest, fees and expenses, whether arising before or
after the commencement of any case with respect to Borrower under the United
States Bankruptcy Code or any similar statute, Guarantor shall be liable
therefor, even if Borrower's liability for such amounts does not, or ceases to,
exist by operation of law.

         This Guaranty is absolute, unconditional and continuing and is in
addition to, but not contingent upon Lender's obtaining, any other guaranty of
the whole or any part of the Guaranteed Obligations. Payment by Guarantor shall
be made to Lender at its office from time to time on demand as Guaranteed
Obligations become due. One or more successive or concurrent actions may be
brought hereon against Guarantor either in the same action in which Borrower or
any other Obligors are sued or in separate actions.

         Payment of all amounts now or hereafter owed to Guarantor by Borrower
or any other Obligor is hereby subordinated in right of payment to the
indefeasible payment in full to Lender of the Guaranteed Obligations and is
hereby assigned to Lender as security therefor. Guarantor hereby irrevocably and
unconditionally waives and relinquishes all statutory, contractual, common law,
equitable and all other claims against Borrower, any collateral for the
Guaranteed Obligations or other assets of Borrower or any other Obligor, for
subrogation, reimbursement, exoneration, contribution, indemnification, setoff
or other recourse in respect of sums paid or payable to Lender by Guarantor
hereunder and Guarantor hereby further irrevocably and unconditionally waives
and relinquishes any and all other benefits which Guarantor might otherwise
directly or indirectly receive or be entitled to receive by reason of any
amounts paid by or collected or due from Guarantor, Borrower or any other
Obligor upon the Guaranteed Obligations or realized from their property.

         All sums at any time owed by Lender to Guarantor or to the credit of
Guarantor and any property of Guarantor on which Lender at any time has a lien
or security interest or of which Lender at any time has possession, shall secure
payment and performance of all Guaranteed Obligations and all other obligations
of Guarantor to Lender however arising.



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         In case proceedings be instituted by or against Borrower or Guarantor
or any other Obligor, in bankruptcy or insolvency, or for reorganization,
arrangement, receivership, or the like, or if Borrower or Guarantor or any other
Obligor calls a meeting of creditors or makes any assignment for the benefit of
creditors, or upon the occurrence of any event which constitutes a default or
event of default under the Financing Agreements, the liability of Guarantor for
the entire Guaranteed Obligations shall mature, even if the liability of
Borrower or any other Obligor therefor does not.

         Guarantor shall continue to be liable hereunder until one of Lender's
officers actually receives a written termination notice by certified mail; but
the giving of such notice shall not relieve Guarantor from liability for any
Guaranteed Obligations incurred before Lender's receipt of such notice of
termination or for post-termination collection expenses and interest pertaining
to any Guaranteed Obligations arising before termination.

         Guarantor agrees that this Guaranty shall remain in full force and
effect or be reinstated, as the case may be, if at any time payment of any of
the Guaranteed Obligations is rescinded or otherwise restored by Lender to
Borrower or to any other person who made such payment, or to the creditors or
creditors' representative of Borrower or such other person.

         Lender's books and records showing the account between Lender and
Borrower shall be admissible in evidence in any action or proceeding as prima
facie proof of the items therein set forth, and any written statements rendered
by Lender to Borrower, to the extent to which no written objection is made
within sixty (60) days after the date thereof, shall be considered correct and
be binding on Guarantor as an account stated for purposes of this Guaranty.

         No delay on Lender's part in exercising any rights hereunder or failure
to exercise the same shall constitute a waiver of such rights. No notice to, or
demand on, Guarantor shall be deemed to be a waiver of the obligation of
Guarantor to take further action without notice or demand as provided herein. No
waiver of any of Lender's rights hereunder, and no modification or amendment of
this Guaranty, shall be deemed to be made by Lender unless the same shall be in
writing, duly signed on Lender's behalf, and each such waiver, if any, shall
apply only with respect to the specific instance involved and shall in no way
impair Lender's rights or the obligations of Guarantor to Lender in any other
respect at any other time.

         Guarantor hereby assumes responsibility for keeping itself informed of
the financial condition of Borrower and any and all endorsers or other
guarantors of any of the Guaranteed Obligations and of all other circumstances
bearing upon the risk of nonpayment of the Guaranteed Obligations or any part
thereof that diligent inquiry would reveal, and Guarantor hereby agrees that
Lender shall have no duty to advise Guarantor of information known to Lender
regarding such condition or any such circumstances.

         This Guaranty is binding upon Guarantor, its successors and assigns and
shall benefit Lender and its successors, endorses, transferees and assigns. All
references to Borrower and Lender herein shall include their respective
successors and assigns. This instrument shall be governed by, and construed and
interpreted in accordance with, the laws of the State of Georgia.



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         Guarantor hereby irrevocably submits and consents and to the
non-exclusive jurisdiction of the State and Federal Courts located in the State
of Georgia with respect to any action or proceeding arising out of this Guaranty
or any matter arising herefrom or relating hereto. Any such action or proceeding
commenced by Guarantor against Lender will be litigated only in a Federal Court
located in the district, or a State Court in the State of Georgia and County of
Fulton and Guarantor waives any objection based on forum non conveniens and any
objection to venue in connection therewith.

         In any such action or proceeding, Guarantor waives personal service of
the summons and complaint or other process and papers therein and agrees that
any process or notice of motion or other application to any of said Courts or a
judge thereof, or any notice in connection with any proceedings hereunder may be
served (i) inside or outside such State by registered or certified mail, return
receipt requested, addressed to Guarantor at the address set forth below or
which Guarantor has previously advised Lender in writing and as indicated in the
records of Lender and service or notice so served shall be deemed complete five
(5) days after the same shall have been posted or (ii) in such other manner as
may be permissible under the rules of said Courts.

         Notwithstanding any other provision of this Guaranty to the contrary,
if the obligations of Guarantor hereunder would otherwise be held or determined
by a court of competent jurisdiction in any action or proceeding involving any
state corporate law or any state or federal bankruptcy, insolvency,
reorganization, moratorium, fraudulent conveyance or other similar law affecting
the rights of creditors generally, to be void, invalid or unenforceable to any
extent on account of the amount of such Guarantor's liability under this
Guaranty, then notwithstanding any other provision of this Guaranty to the
contrary, the amount of such liability shall, without any further action by
Guarantor or any other person or entity, be automatically limited and reduced to
the highest amount that is valid and enforceable as determined in such action or
proceeding.

         This Guaranty may be executed in any number of counterparts and by
different parties to this Agreement on separate counterparts, each of which,
when so executed, shall be deemed an original, but all such counterparts shall
constitute one and the same agreement.

         TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW, GUARANTOR AND LENDER
WAIVE ALL RIGHTS TO TRIAL BY JURY IN ANY ACTION OR PROCEEDING INSTITUTED BY
EITHER OF THEM AGAINST THE OTHER WHICH PERTAINS DIRECTLY OR INDIRECTLY TO THIS
GUARANTY, ANY ALLEGED TORTIOUS CONDUCT BY GUARANTOR OR LENDER, OR, IN ANY WAY,
DIRECTLY OR INDIRECTLY, ARISING OUT OF OR RELATED TO THE RELATIONSHIP BETWEEN
GUARANTOR AND LENDER OR BORROWER AND LENDER. IN NO EVENT WILL LENDER BE LIABLE
FOR LOST PROFITS OR OTHER SPECIAL OR CONSEQUENTIAL DAMAGES.

         GUARANTOR HEREBY ACKNOWLEDGES THAT IT HAS BEEN ADVISED BY COUNSEL OF
ITS OWN SELECTION IN THE NEGOTIATION, EXECUTION AND DELIVERY OF THIS GUARANTY,
THAT LENDER HAS NO FIDUCIARY RELATIONSHIP TO GUARANTOR (BUT RATHER THE
RELATIONSHIP BETWEEN LENDER AND GUARANTOR IS SOLELY THAT OF CREDITOR AND
DEBTOR), AND THAT NO JOINT VENTURE EXISTS BETWEEN LENDER AND BORROWER OR BETWEEN
LENDER AND GUARANTOR.



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         IN WITNESS WHEREOF, Guarantor has executed and delivered this Guaranty
under seal on day and year first above written.


ATTEST:                             HAYES CORPORATION, FORMERLY KNOWN AS
                                    ACCESS BEYOND, INC.

         /s/                        By:      /s/ Ronald Howard
----------------------                  -----------------------------------
Secretary
                                    Title:   /s/ Vice Chairman-CEO
[CORPORATE SEAL]                          ---------------------------------

                                    Address: 1300 Quince Orchard Boulevard
                                             Gaithersburg, Maryland  20878


STATE OF Georgia   )
                   ) ss.:
COUNTY OF Gwinnett )

         On this 2nd day of January, 1998, before me personally came Ronald
Howard, to me known, who stated that he is the Vice Chairman-CEO of HAYES
CORPORATION, FORMERLY KNOWN AS ACCESS BEYOND, INC. described in and which
executed the foregoing instrument and that he signed his name thereto by order
of the Board of Directors of said corporation.

                                                /s/ Kim Gallagher
                                            -------------------------
                                            Notary Public
                                            My Commission Expires:

                                               March 12, 2000
                                            -------------------------
                                            [NOTARIAL SEAL]













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