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                                                                   Exhibit 10.75

                         FULL RECOURSE PROMISSORY NOTE

$75,000.00                                                    September 18, 2000
                                                        Walnut Creek, California

        FOR VALUE RECEIVED, James R. Weaver ("Maker"), an individual, promises
to pay Tier Technologies, Inc., a California corporation ("Holder"), or order,
at 1350 Treat Boulevard, Suite 250, Walnut Creek, California or such other place
as Holder may from time to time designate, in lawful money of the United States,
the principal sum of seventy-five thousand dollars ($75,000.00), plus interest
thereon from the date of issuance until paid in full, as set forth below.

1.      Interest. Interest on the principal sum of this Note shall accrue at the
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        rate of 6.13% per annum, compounded annually, based on a 365-day year
        and the actual number of days elapsed. Interest shall be payable by
        Maker on a quarterly basis and, except as provided in Paragraph 2 below,
        shall not be forgiven.

2.      Payments/Forgiveness. The entire principal sum and all accrued but
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        unpaid interest and any other sums payable hereunder shall be due and
        payable in full on September 18, 2005; provided, however, that upon the
        relocation of the Maker to the Greater Boston Metropolitan Area, the
        principal sum advanced and related future imputed interest shall be
        forgiven ratably over the remaining term of this Note. In the event
        Maker's employment with the Company terminates prior to September 18,
        2005, the entire remaining principal sum and all accrued but unpaid
        interest and any other sums payable hereunder shall be immediately due
        and payable.

3.      Prepayment. This Note may be prepaid in whole or in part, at any time,
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        without penalty or premium.

4.      Application of Payments. All payments received by Holder shall be
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        applied first to accrued interest, then to other charges due with
        respect to this Note, and then to then-unpaid principal balance.

5.      Default and Remedies.
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        a.     Default. Maker will be in default under this Note if (i) Maker
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               fails to make a payment of principal and/or interest hereunder
               when due, or (ii) Maker breaches any other covenant or agreement
               under this Note.

        b.     Remedies. Upon Maker's default, Holder may (i) upon fifteen (15)
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               days' written notice to Maker, declare the entire principal sum
               and all accrued and unpaid interest hereunder immediately due and
               payable and (ii) exercise any and all remedies provided under
               applicable law. Maker accepts and agrees that this Note is a full
               recourse Note and that Holder may exercise any and all remedies
               available to it under law.

6.      Waivers. Maker, and any endorsers or guarantors hereof, severally waive
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        diligence, presentment, protest and demand and also notice of dishonor
        of this Note, and expressly

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        agrees that this Note, or any payment hereunder, may be extended from
        time to time without notice, all without in any way affecting the
        liability of Maker or any endorsers or guarantors hereof. No extension
        of time for the payment of this Note, or any installment hereof, agreed
        to by Holder with any person now or hereafter liable for the payment of
        this Note, shall affect the original liability of Maker under this Note,
        even if Maker is not a party to such agreement. Holder may waive its
        right to require performance of or compliance with any term, covenant or
        condition of this Note only by express written waiver.

7.      Miscellaneous.
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        a.     Maker shall pay all costs, including, without limitation,
               reasonable attorneys' fees and costs incurred by Holder in
               collecting the sums due hereunder, whether or not any legal
               action is actually filed, litigated or prosecuted to judgment or
               award. In the event of any action or legal proceeding concerning
               this Note or the enforcement of any rights hereunder, Holder
               shall be entitled to, in addition to any other relief to which
               Holder may be entitled, all legal and court costs and expenses,
               including reasonable attorneys' fees, incurred by Holder in
               connection with such action.

        b.     This Note may be modified only by a written agreement executed by
               Maker and Holder.

        c.     This Note shall be governed by California law.

        d.     The terms of this Note shall inure to the benefit of and bind
               Maker and Holder and their respective heirs, legal
               representatives and successors and assigns.

        e.     Time is of the essence with respect to all matters set forth in
               this Note.

        f.     If this Note is destroyed, lost or stolen, Maker will deliver a
               new Note to Holder on the same terms and conditions as this Note,
               with a notation of the unpaid principal and accrued and unpaid
               interest in substitution of the prior Note. Holder shall furnish
               to Maker reasonable evidence that the Note was destroyed, lost or
               stolen and any security or indemnity that may be reasonably
               required by Maker in connection with the replacement of this
               Note.

IN WITNESS WHEREOF, Maker has executed this Note as of the date and year first
above written.

                                            APPROVED: Tier Technologies, Inc.


Maker: /s/ James R. Weaver                      By: /s/ Laura B. DePole
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      James R. Weaver                           Laura B. DePole
                                                Senior Vice President and Chief
                                                Financial Officer

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