EXHIBIT 10.91

EPICOR SOFTWARE CORPORATION

MANAGEMENT RETENTION AGREEMENT

This Management Retention Agreement (the “Agreement”) is made and entered into
effective as of May 26, 2006 (the “Effective Date”), by and between L. George
Klaus (the “Executive”) and Epicor Software Corporation (the “Company”). Certain
capitalized terms used in this Agreement are defined in Section 1 below.

RECITALS

WHEREAS, Executive previously entered into a management retention agreement with
the Company on December 17, 2001 (the “Original Agreement”);

WHEREAS, Executive agrees to enter into this Agreement which will supersede the
Original Agreement in its entirety; and

NOW, THEREFORE, in consideration of the mutual covenants and promises set forth
herein and for other good and valuable consideration, the receipt of and
sufficiency of which are hereby acknowledged, Company and the Executive agree as
follows:

1. Definitions. The following terms referred to in this Agreement shall have the
following meanings:

(a) “Cause” means (i) any act of personal dishonesty taken by Executive in
connection with his responsibilities as an employee which is intended to result
in substantial personal enrichment of Executive; (ii) Executive’s conviction of
a felony which the Board reasonably believes has had or will have a material
detrimental effect on the Company’s reputation or business; (iii) a willful act
by Executive which constitutes misconduct and is injurious to the Company; or
(iv) continued willful violations by Executive of Executive’s obligations to the
Company after there has been delivered to Executive a written demand for
performance from the Company which describes the basis for the Company’s belief
that Executive has not substantially performed his duties.

(b) “Disability” means Executive’s inability due to any physical or mental
condition to perform a substantial portion of his employment duties to the
Company for twenty-four (24) or more consecutive weeks.

(c) “Involuntary Termination” means, without Executive’s express written
consent, (i) a significant reduction of Executive’s duties, position or
responsibilities relative to Executive’s duties, position or responsibilities in
effect immediately prior to such reduction, or the removal of Executive from
such position, duties and responsibilities, unless Executive is provided with
comparable duties, position and responsibilities; (ii) a reduction by the
Company of Executive’s base salary as in effect immediately prior to such
reduction unless such reduction is made pursuant to and proportionately with any
Company policy applicable to similarly-situated Company executives;

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(iii) the relocation of Executive to a facility or a location more than one
hundred (100) miles from his current location; (iv) any purported termination of
Executive by the Company which is not effected for Cause or for which the
grounds relied upon are not valid; (v) Executive’s death or Disability; or
(vi) the failure of the Company to obtain the assumption of this Agreement by
any successors contemplated in Section 14 below.

(d) “Retirement” means Executive’s termination of his employment with the
Company at the end of the Employment Term, or voluntarily by Executive prior to
the Retirement Date provided that such earlier Retirement is with the approval
and consent of the Company’s Board and does not arise for Cause.

2. Term of Agreement. Executive hereby accepts further employment with the
Company for a period beginning on the Effective Date and ending on December 31,
2007 (“Employment Term”) on the terms and conditions set forth herein.

3. At-Will Employment. The Company and Executive acknowledge that Executive’s
employment is and shall continue to be at-will, as defined under applicable law.
If Executive’s employment terminates for any reason, Executive shall not be
entitled to any payments, benefits, damages, awards or compensation other than
as provided by this Agreement, or as may otherwise be established under the
Company’s then existing employee benefit plans or policies at the time of
termination.

4. Base Salary. During the Employment Term, the Company will pay Executive a
salary at an annualized rate of $736,403 as compensation for his services (the
“Base Salary”). The Base Salary will be paid periodically in accordance with the
Company ‘s normal payroll practices and be subject to the usual, required
withholdings. The Base Salary will not be increased during the Employment Term
without the prior written approval of the Company’s Board of Directors.

5. Annual Incentive. Executive will continue to be eligible to receive annual
cash bonus payments under the Company’s cash bonus plan for key employees as in
effect on the Effective Date. The bonus will be paid on fiscal year basis based
on a performance plan agreed to between the Executive and the Board of Directors
of the Company.

6. Restricted Stock Grant. Executive will be granted a right to purchase four
hundred thousand (400,000) shares of restricted Company common stock (the
“Restricted Stock Grant”). The Restricted Stock Grant will provide that the
restrictions on the stock shall lift during the Employment Term according to the
terms of the restricted stock incentive program to be approved by the Company’s
Compensation Committee, subject to the Executive’s continued service to the
Company on such dates. The Restricted Stock Grant will also be subject to the
terms, definitions and provisions of the Company’s 2005 Stock Incentive Plan
(the “Plan”) and the restricted stock agreement by and between Executive and the
Company (the “Restricted Stock Agreement”), both of which documents are
incorporated herein by reference.

 

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7. Severance Benefits. Upon the occurrence of an Involuntary Termination,
Executive shall be entitled to only the following benefits:

(a) twelve (12) months of Executive’s Base Salary as in effect as of the date of
the Involuntary Termination, to be paid periodically in accordance with the
Company’s normal payroll policies;

(b) any bonus that would have been earned by Executive in the twelve (12) month
period following the date of the Involuntary Termination (as determined by the
Company in its discretion); and

(c) the Executive, Executive’s spouse and Executive’s dependents who are
participating in Company group medical or dental plans on the date of
Executive’s termination of service (“Covered Persons”) shall be entitled to
continued participation in such plans, as they may be modified by the Company
from time to time, at no additional after-tax cost to Executive (or Executive’s
spouse or dependents, as applicable) other than Executive would have were he an
employee, from year to year, for the remainder of the lifetimes of each Covered
Person (or with respect to dependents of Executive, until the earlier of i) the
death of both Executive and Executive’s spouse covered hereunder; ii) the time
such dependents reach eighteen (18) years of age if they do not continue
thereafter as full time students; or iii) through the period from 18 years of
age up to 25 years of age during which such dependents remain full time
students); provided, however, that such coverage shall be suspended for any
period during which any Covered Persons obtain or are covered by other
comparable group health coverage. Executive shall notify Company when any other
group health coverage for Covered Persons begins or ends. In the event that
Executive and/or Executive’s spouse and dependents, as applicable, are not
eligible to continue their participation in the Company’s group medical or
dental plans, then alternatively, such individuals shall be entitled to receive
equivalent coverage under a separate plan according to the same terms and
conditions as indicated herein.

8. Other Termination. If the Executive’s employment with the Company terminates
other than as a result of an Involuntary Termination or Retirement, then the
Executive shall not be entitled to receive severance or other benefits
hereunder, but may be eligible for those benefits (if any) as may then be
established under the Company’s then existing severance and benefits plans and
policies at the time of such termination.

9. Retirement. In the event Executive’s employment with the Company terminates
by reason of Executive’s Retirement, and provided that Executive at the time of
such Retirement has substantially completed a successful CEO succession plan
acceptable to the Company’s Board of Directors, then the Covered Persons shall
be entitled to continued participation in the Company’s group medical or dental
plans, as they may be modified by the Company from time to time, at no
additional after-tax cost to Executive (or Executive’s spouse or dependents, as
applicable) other than Executive would have were he an employee, from year to
year, for the remainder of the lifetimes of each Covered Person (or with respect
to dependents of Executive, until the earlier of i) the death of both Executive
and Executive’s spouse covered hereunder; ii) the time such dependents reach
eighteen (18) years of age if they do not continue thereafter as full time
students; or iii) through the period from 18 years of age up to 25 years of age
during which such dependents remain full time students); provided, however, that
such coverage shall be suspended for any period during which any Covered Persons
obtain or are covered by other comparable group health coverage. Executive shall

 

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notify Company when any other group health coverage for Covered Persons begins
or ends. In the event that Executive and/or Executive’s spouse and dependents,
as applicable, are not eligible to continue their participation in the Company’s
group medical or dental plans, then alternatively, such individuals shall be
entitled to receive equivalent coverage under a separate plan according to the
same terms and conditions as indicated herein.

10. Accrued Wages and Vacation; Expenses. Without regard to the reason for, or
the timing of, Executive’s termination of employment: (i) the Company shall pay
Executive any unpaid base salary due for periods prior to any termination of
employment; (ii) the Company shall pay Executive all of his accrued and unused
vacation, if any, through any termination of employment; and (iii) following
submission of proper expense reports by Executive, the Company shall reimburse
Executive for all expenses reasonably and necessarily incurred by Executive in
connection with the business of the Company prior to any termination of
employment. Executive acknowledges that as of the Effective Date, he does not
have any accrued vacation as mandated by established Company policy. These
payments shall be made promptly upon termination and within the period of time
mandated by law.

11. Golden Parachute Excise Tax Gross-Up. In the event that the severance and
other benefits provided for in this Agreement constitute “parachute payments”
within the meaning of Section 280G of the Internal Revenue Code of 1986, as
amended (the “Code”) and will be subject to the excise tax imposed by
Section 4999 of the Code, then Executive shall receive (i) a payment from the
Company sufficient to pay such excise tax, and (ii) an additional payment from
the Company sufficient to pay the excise tax and federal and state income taxes
arising from the payments made by the Company to Executive pursuant to this
sentence. Unless the Company and Executive otherwise agree in writing, the
determination of Executive’s excise tax liability and the amount required to be
paid under this Section shall be made in writing by the Company’s independent
accountants (the “Auditors”). In the event that the excise tax incurred by
Executive is determined by the Internal Revenue Service to be greater or lesser
than the amount so determined by the Auditors, the Company and Executive agree
to promptly make such additional payment, including interest and any tax
penalties, to the other party as the Auditors reasonably determine is
appropriate to ensure that the net economic effect to Executive under this
Section, on an after-tax basis, is as if the Code Section 4999 excise tax did
not apply to Executive. For purposes of making the calculations required by this
Section, the Auditors may make reasonable assumptions and approximations
concerning applicable taxes and may rely on interpretations of the Code for
which there is a “substantial authority” tax reporting position. The Company and
Executive shall furnish to the Auditors such information and documents as the
Auditors may reasonably request in order to make a determination under this
Section. The Company shall bear all costs the Auditors may reasonably incur in
connection with any calculations contemplated by this Section.

12. Conditions to Receipt of Severance.

(a) Separation Agreement and Release of Claims. The receipt of any severance
pursuant to Section 7 or Section 9 will be subject to Executive signing and not
revoking a separation agreement and release of claims in a form reasonably
acceptable to the Company. No severance will be paid or provided until the
separation agreement and release agreement becomes effective.

 

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(b) Nondisparagement. During the Employment Term and while the Executive is
receiving the Base Salary or continued medical benefits under Section 7 or
Section 9 (“Severance Period”), Executive will not knowingly disparage,
criticize, or otherwise make any derogatory statements regarding the Company,
its directors, or its officers. The Company will instruct its officers and
directors to not knowingly disparage, criticize, or otherwise make any
derogatory statements regarding the Executive during the Employment Term and
Severance Period. Notwithstanding the foregoing, nothing contained in this
agreement will be deemed to restrict the Executive, the Company or any of the
Company’s current or former officers and/or directors from providing information
to any governmental or regulatory agency (or in any way limit the content of any
such information) to the extent they are requested or required to provide such
information pursuant to applicable law or regulation.

(c) Other Requirements. Executive’s receipt of continued severance payments will
be subject to Executive continuing to comply with the terms of the Company’s
Confidential/Proprietary Information Agreement and the provisions of this
Section 12.

13. Code Section 409A. To the extent required by Section 409A(a)(2)(B)(i) of the
Code to avoid taxation of any severance payments hereunder under Section 409A of
the Code, the payments to which Executive would otherwise be entitled during the
first six months following the date of Employee’s separation from service with
the Company shall be accumulated and paid as of the first payment date in the
seventh month following the separation from service.

14. Successors.

(a) Company’s Successors. Any successor to the Company (whether direct or
indirect and whether by purchase, lease, merger, consolidation, liquidation or
otherwise) to all or substantially all of the Company’s business and/or assets
shall assume the Company’s obligations under this Agreement and agree expressly
to perform the Company’s obligations under this Agreement in the same manner and
to the same extent as the Company would be required to perform such obligations
in the absence of a succession. For all purposes under this Agreement, the term
“Company” shall include any successor to the Company’s business and/or assets
which executes and delivers the assumption agreement described in this
subsection or which becomes bound by the terms of this Agreement by operation of
law.

(b) Executive’s Successors. Without the written consent of the Company,
Executive shall not assign or transfer this Agreement or any right or obligation
under this Agreement to any other person or entity. Notwithstanding the
foregoing, the terms of this Agreement and all rights of Executive hereunder
shall inure to the benefit of, and be enforceable by, Executive’s personal or
legal representatives, executors, administrators, successors, heirs,
distributees, devisees and legatees.

15. Notices.

(a) General. Notices and all other communications contemplated by this Agreement
shall be in writing and shall be deemed to have been duly given when personally

 

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delivered or when mailed by U.S. registered or certified mail, return receipt
requested and postage prepaid. In the case of Executive, mailed notices shall be
addressed to him at the home address that he most recently communicated to the
Company in writing. In the case of the Company, mailed notices shall be
addressed to its corporate headquarters, and all notices shall be directed to
the attention of its Secretary.

(b) Notice of Termination. Any termination by the Company for Cause or by
Executive as a result of a voluntary resignation, Involuntary Termination or
Retirement shall be communicated by a notice of termination to the other party
hereto given in accordance with this Section. Such notice shall indicate the
specific termination provision in this Agreement relied upon, shall set forth in
reasonable detail the facts and circumstances claimed to provide a basis for
termination under the provision so indicated, and shall specify the termination
date (which shall be not more than 30 days after the giving of such notice). The
failure by Executive to include in the notice any fact or circumstance which
contributes to a showing of Involuntary Termination shall not waive any right of
Executive hereunder or preclude Executive from asserting such fact or
circumstance in enforcing his rights hereunder.

16. Arbitration.

(a) Any dispute or controversy arising out of, relating to, or in connection
with this Agreement, or the interpretation, validity, construction, performance,
breach, or termination thereof, shall be settled by binding arbitration to be
held in Orange County, California in accordance with the National Rules for the
Resolution of Employment Disputes then in effect of the American Arbitration
Association (the “Rules”). The arbitrator may grant injunctions or other relief
in such dispute or controversy. The decision of the arbitrator shall be final,
conclusive and binding on the parties to the arbitration. Judgment may be
entered on the arbitrator’s decision in any court having jurisdiction.

(b) The arbitrator(s) shall apply California law to the merits of any dispute or
claim, without reference to conflicts of law rules. The arbitration proceedings
shall be governed by federal arbitration law and by the Rules, without reference
to state arbitration law. Executive hereby consents to the personal jurisdiction
of the state and federal courts located in California for any action or
proceeding arising from or relating to this Agreement or relating to any
arbitration in which the parties are participants.

(c) Executive understands that nothing in this Section modifies Executive’s
at-will employment status. Either Executive or the Company can terminate the
employment relationship at any time, with or without Cause.

(d) EXECUTIVE HAS READ AND UNDERSTANDS THIS SECTION, WHICH DISCUSSES
ARBITRATION. EXECUTIVE UNDERSTANDS THAT SUBMITTING ANY CLAIMS ARISING OUT OF,
RELATING TO, OR IN CONNECTION WITH THIS AGREEMENT, OR THE INTERPRETATION,
VALIDITY, CONSTRUCTION, PERFORMANCE, BREACH OR TERMINATION THEREOF TO BINDING
ARBITRATION, CONSTITUTES A WAIVER OF EXECUTIVE’S RIGHT TO A JURY TRIAL AND
RELATES TO THE

 

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RESOLUTION OF ALL DISPUTES RELATING TO ALL ASPECTS OF THE EMPLOYER/EXECUTIVE
RELATIONSHIP, INCLUDING BUT NOT LIMITED TO, THE FOLLOWING CLAIMS:

(i) ANY AND ALL CLAIMS FOR WRONGFUL DISCHARGE OF EMPLOYMENT; BREACH OF CONTRACT,
BOTH EXPRESS AND IMPLIED; BREACH OF THE COVENANT OF GOOD FAITH AND FAIR DEALING,
BOTH EXPRESS AND IMPLIED; NEGLIGENT OR INTENTIONAL INFLICTION OF EMOTIONAL
DISTRESS; NEGLIGENT OR INTENTIONAL MISREPRESENTATION; NEGLIGENT OR INTENTIONAL
INTERFERENCE WITH CONTRACT OR PROSPECTIVE ECONOMIC ADVANTAGE; AND DEFAMATION.

(ii) ANY AND ALL CLAIMS FOR VIOLATION OF ANY FEDERAL STATE OR MUNICIPAL STATUTE,
INCLUDING, BUT NOT LIMITED TO, TITLE VII OF THE CIVIL RIGHTS ACT OF 1964, THE
CIVIL RIGHTS ACT OF 1991, THE AGE DISCRIMINATION IN EMPLOYMENT ACT OF 1967, THE
AMERICANS WITH DISABILITIES ACT OF 1990, THE FAIR LABOR STANDARDS ACT, THE
CALIFORNIA FAIR EMPLOYMENT AND HOUSING ACT, AND LABOR CODE SECTION 201, et seq;

(iii) ANY AND ALL CLAIMS ARISING OUT OF ANY OTHER LAWS AND REGULATIONS RELATING
TO EMPLOYMENT OR EMPLOYMENT DISCRIMINATION.

17. Miscellaneous Provisions.

(a) No Duty to Mitigate. Executive shall not be required to mitigate the amount
of any payment contemplated by this Agreement, nor shall any such payment be
reduced by earnings that Executive may receive from any other source, except
with respect to the suspension of any post-termination medical coverage while
Executive has alternative coverage as described in Section 7(c) and Section 9.

(b) Waiver. No provision of this Agreement may be modified, waived or discharged
unless the modification, waiver or discharge is agreed to in writing and signed
by Executive and by an authorized officer of the Company (other than Executive).
No waiver by either party of any breach of, or of compliance with, any condition
or provision of this Agreement by the other party shall be considered a waiver
of any other condition or provision or of the same condition or provision at
another time.

(c) Integration. This Agreement and any outstanding stock option agreements,
restricted stock purchase agreements and loan agreements referenced herein
represent the entire agreement and understanding between the parties as to the
subject matter herein and supersede all prior or contemporaneous agreements,
whether written or oral, with respect to this Agreement, including but not
limited to the Original Agreement and the offer letter entered into by and
between the Company and Executive on February 7th, 1996 (the “Offer Letter”) and
any stock option agreement, restricted stock purchase agreement or loan
agreement. Executive agrees and acknowledges that in the event of any conflict,
redundancy or discrepancy between the terms and conditions of the Offer Letter
and this Agreement, the terms and conditions of this Agreement shall govern.

 

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(d) Choice of Law. The validity, interpretation, construction and performance of
this Agreement shall be governed by the internal substantive laws, but not the
conflicts of law rules, of the State of California.

(e) Severability. The invalidity or unenforceability of any provision or
provisions of this Agreement shall not affect the validity or enforceability of
any other provision hereof, which shall remain in full force and effect.

(f) Employment Taxes. All payments made pursuant to this Agreement shall be
subject to withholding of applicable income and employment taxes.

(g) Counterparts. This Agreement may be executed in counterparts, each of which
shall be deemed an original, but all of which together will constitute one and
the same instrument.

 

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IN WITNESS WHEREOF, each of the parties has executed this Agreement, in the case
of the Company by its duly authorized officer, as of the day and year first
above written.

 

COMPANY:

   

EPICOR SOFTWARE CORPORATION

     

By:

 

/s/ John D. Ireland

     

Title:

 

General Counsel and Vice President

EXECUTIVE:

            

Signature

     

/s/ L. George Klaus

     

L. George Klaus

     

Printed Name

 

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