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                                                          EXHIBIT 4.19

                                   GUARANTEE

IN CONSIDERATION OF Toshiba Information Systems (UK) Limited (registered number
918861), a company incorporated under the laws of England, whose registered
office is at Toshiba Court, Weybridge Business Park, Addlestone Road,
Weybridge, Surrey KT15 2UL, United Kingdom ("Toshiba"), agreeing to enter and
entering into an agreement ("the Agreement") with Interface Systems
International Limited (registered number 2100227), a company incorporated under
the laws of England, whose registered office is at 881/882 Plymouth Road,
Slough, Berkshire, SL1 4LP, United Kingdom ("the Dealer"), to supply Toshiba
portable computers to the Dealer.

1)   Interface Systems Inc. ("the Guarantor"), (registered number 38-1857379)
     a company incorporated under the laws of the State of Delaware, whose
     registered office is at 5855 Interface Drive, Ann Arbor, Michigan 48103,
     USA, and which is the sole shareholder in the Dealer.

            HEREBY GUARANTEES to Toshiba the payment of all monies now or at
            any time hereafter to become due to Toshiba under the Agreement,
            but so that the Guarantor's liability to Toshiba is in no event to
            exceed the sum of two million pounds sterling (L.2,000,000).

2)   The Guarantor HEREBY AGREES as follows:

      A.   Toshiba is to be at liberty to grant to the Dealer such
           extension of credit or time for payment, or other indulgences as
           Toshiba thinks proper without in any way discharging or impairing
           the Guarantor's liability toward Toshiba under this Guarantee.

      B.   The Guarantee is to be a continuing guarantee.

      C.   For all purposes the liability of the Guarantor to Toshiba
           under this Guarantee, every sum of money which may from time to time
           become due or owing to Toshiba shall be deemed to continue to be due
           and owing to Toshiba by the Dealer until the same be actually repaid
           to Toshiba, notwithstanding the bankruptcy or winding up of the
           Dealer.  All dividends, compositions and payments received by the
           Dealer or from the Dealer's estate, whether in bankruptcy or
           otherwise, or if the Dealer is a company, in the event of
           liquidation, wind-up or reconstruction, shall be taken and applied
           by Toshiba as payments in gross and the right of the Guarantor to be
           subrogated to Toshiba shall not arise until Toshiba has received the
           full amount of all its claims against the Dealer, and this Guarantee
           shall be a security to Toshiba for the payment of any ultimate
           balance that may remain due to Toshiba.

      D.   When the Dealer is a partnership or individual this Guarantee
           shall not be affected by any change, whether by death, retirement,
           or addition, etc., in respect of the trading style of the firm or by
           any other means, but shall remain valid continuing and

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           effective as folly and in all respects as if, in the case of a
           partnership the persons constituting such partnership or, in the
           case of an individual his executors or administrators, at the date
           of any demand for payment made by Toshiba under this Guarantee or
           at any time previously were the same at the date hereof.

      E.   In order to give effect to the Guarantee, the Guarantor
           declares that Toshiba shall be at liberty to act as though it were
           the principal debtor and the Guarantor hereby waives all and any of
           its rights as Guarantor which may at any time be inconsistent with
           any of the above provisions.

      F.   The Guarantor may cancel this Guarantee prospectively as to
           future orders by the Dealer upon thirty (30) days prior written
           notice to Toshiba.  However, no such cancellation shall impair or
           affect sums guaranteed by the Guarantor hereunder prior to the
           giving of such notice.

           Such notice shall be sent by Air Mail letter for the attention of:

           C M Lintell  -  Company Secretary, Toshiba Information Systems (UK)
           Ltd. Toshiba Court, Weybridge Business Park, Addlestone Road,
           Weybridge, Surrey  KT15  2UL, UK

           The notice shall simultaneously be addressed to the above party by
           facsimile using the following number 44-932829091.

      G.   Toshiba shall serve notice of its intention to enforce the
           Guarantee by Air Mail letter for the attention of:

           Name David O. Schupp             Title             Finance, Treasurer

           Address   5855 Interface Drive, Ann Arbor, Michigan 48103

           The notice shall simultaneously be addressed to the above party by
           facsimile using the following number 313-769-5900.

      H.   This Guarantee replaces any prior Guarantees from Interface
           Systems, Inc. that are held by Toshiba Information Systems (UK)
           Limited.



 Dated:     November 18, 1994               Signed:  /s/ David O. Schupp
            ----------------------------             --------------------------

 Position:  Treasurer                       Name:    David O. Schupp
            ----------------------------             --------------------------



UNDER THE COMMON SEAL OF INTERFACE SYSTEMS INC.