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                                 UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
 
                             WASHINGTON, D.C. 20549
                            ------------------------
 
   
                                  FORM 10-K/A
                               (AMENDMENT NO. 1)
    
 
(MARK ONE)
 
  /X/    ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
         EXCHANGE ACT OF 1934
 
                    FOR THE FISCAL YEAR ENDED JUNE 30, 1998.
 
                                       OR
 
  / /    TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
         SECURITIES EXCHANGE ACT OF 1934
 
           FOR THE TRANSITION PERIOD FROM            TO            .
 
                        COMMISSION FILE NUMBER: 0-19024
                            ------------------------
 
                              SYMIX SYSTEMS, INC.
             (Exact name of registrant as specified in its charter)
 
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<S>                                                     <C>
                         OHIO                                      31-1083175
   (State or other jurisdiction of incorporation or     (I.R.S. Employer Identification
                    organization)                                     No.)
 
            2800 CORPORATE EXCHANGE DRIVE
                    COLUMBUS, OHIO                                   43231
       (Address of principal executive offices)                    (Zip Code)
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       Registrant's telephone number, including area code: (614) 523-7000
                            ------------------------
 
          Securities registered pursuant to Section 12(b) of the Act:
 
                                      NONE
          Securities registered pursuant to Section 12(g) of the Act:
 
                           COMMON SHARES NO-PAR VALUE
                                 Title of Class
                            ------------------------
 
    Indicate by check mark whether the registrant: (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days.  Yes _X_ No ____
 
    Indicate by check mark if disclosure of delinquent filers pursuant to Item
405 of Regulation S-K (Section 229.405 of this chapter) is not contained herein,
and will not be contained, to the best of registrant's knowledge, in definitive
proxy or information statements incorporated by reference in Part III of this
Form 10-K or any amendment to this Form 10-K. [  ]
 
    The aggregate market value of the voting and non-voting common equity held
by non-affiliates of the registrant at September 22, 1998 was $75,335,545.
 
    The number of common shares outstanding at September 22, 1998 was 6,507,054.
 
                      DOCUMENTS INCORPORATED BY REFERENCE:
 
    (1) The Registrant's Definitive Proxy Statement for its Annual Meeting of
       Shareholders to be held on November 11, 1998 is incorporated by reference
       into Part III of this Annual Report on Form 10-K.
 
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                                    PART IV
 
ITEM 14.  EXHIBITS, FINANCIAL STATEMENT SCHEDULES, AND REPORTS ON FORM 8-K.
 
(a) DOCUMENTS FILED AS PART OF THIS REPORT:
 
    1   Financial Statements
 
   
        See Item 8 of the Annual Report on Form 10-K.--Index to Financial
       Statements and Financial Statement Schedules
    
 
    2   Financial Statement Schedules
 
   
        See Item 8 of the Annual Report on Form 10-K.--Index to Financial
       Statements and Financial Statement Schedules
    
 
    3   Exhibits:
 
   
        See Exhibit Index of this Annual Report on Form 10-K/A.
    
 
(b) REPORTS ON FORM 8-K:
 
    None.
 
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                                   SIGNATURES
    
 
   
    Pursuant to the requirements of Section 13 or 15(d) of the Securities
Exchange Act of 1934, the registrant has duly caused this report to be signed on
its behalf by the undersigned, thereunto duly authorized, on the 14th day of
October, 1998.
    
 
   
                                SYMIX SYSTEMS, INC.
 
                                By:            /s/ LAWRENCE W. DELEON
                                     -----------------------------------------
                                                 Lawrence W. DeLeon
                                      VICE PRESIDENT, CHIEF FINANCIAL OFFICER
                                                   AND SECRETARY
 
    
 
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                               INDEX TO EXHIBITS
 
   
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   EXHIBIT NO.                        DESCRIPTION                                           PAGE
-----------------  -------------------------------------------------  -------------------------------------------------
<C>                <S>                                                <C>
         3(a)(1)   Amended Articles of Incorporation of Symix         Incorporated by reference to Exhibit 3(a)(1) to
                   Systems, Inc. (as filed on February 8, 1991)       Registrant's Annual Report on Form 10-K for the
                                                                      fiscal year ended June 30, 1997
 
         3(a)(2)   Certificate of Amendment to the Amended Articles   Incorporated by reference to Exhibit 3(a)(2) to
                   of Incorporation of Symix Systems, Inc. (as filed  Registrant's Annual Report on Form 10-K for the
                   on July 16, 1996)                                  fiscal year ended June 30, 1997
 
         3(a)(3)   Amended Articles of Incorporation of Symix         Incorporated herein by reference to Exhibit
                   Systems, Inc. (reflecting amendments through July  3(a)(3) to Registrant's Annual Report on Form
                   16, 1996, for purposes of SEC reporting            10-K for the fiscal year ended June 30, 1997
                   compliance only)
 
         3(b)      Amended Regulations of Symix Systems, Inc.         Incorporated herein by reference to Exhibit 3(b)
                                                                      to the Registration Statement on Form S-1 of
                                                                      Registrant, filed February 12, 1991 (Registration
                                                                      No. 33-38878)
 
         4(a)(1)   Amended Articles of Incorporation of Symix         Incorporated by reference to Exhibit 3(a)(1) to
                   Systems, Inc. (as filed on February 8, 1991)       Registrant's Annual Report on Form 10-K for the
                                                                      fiscal year ended June 30, 1997
 
         4(a)(2)   Certificate of Amendment to the Amended Articles   Incorporated by reference to Exhibit 3(a)(2) to
                   of Incorporation of Symix Systems, Inc. (as filed  Registrant's Annual Report on Form 10-K for the
                   on July 16, 1996)                                  fiscal year ended June 30, 1997
 
         4(a)(3)   Amended Articles of Incorporation of Symix         Incorporated herein by reference to Exhibit
                   Systems, Inc. (reflecting amendments through July  3(a)(3) to Registrant's Annual Report on Form
                   16, 1996, for purposes of SEC reporting            10-K for the fiscal year ended June 30, 1997
                   compliance only)
 
         4(b)      Amended Regulations of Symix Systems, Inc.         Incorporated herein by reference to Exhibit 3(b)
                                                                      to the Registration Statement on Form S-1 of
                                                                      Registrant, filed February 12, 1991 (Registration
                                                                      No. 33-38878)
 
         4(c)      Share Exchange Agreement dated January 9, 1997     Incorporated herein by reference to Exhibit 99 to
                                                                      Registrant's Current Report on Form 8-K dated
                                                                      January 9, 1997
 
        10(a)      Lease Agreement dated April 3, 1991 for office     Incorporated herein by reference to Exhibit 10(c)
                   located at 2800 Corporate Exchange Drive,          to Registrant's Annual Report on Form 10-K for
                   Columbus, Ohio                                     the fiscal year ended June 30, 1991
 
        10(b)      Lease Amendment to office located at 2800          Incorporated herein by reference to Exhibit 10(b)
                   Corporate Exchange Drive, Columbus, Ohio           to Registrant's Annual Report on Form 10-K for
                                                                      the fiscal year ended June 30, 1998
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   EXHIBIT NO.                        DESCRIPTION                                           PAGE
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<C>                <S>                                                <C>
        10(c)      Second Lease Amendment to office located at 2800   Incorporated herein by reference to Exhibit 10(c)
                   Corporate Exchange Drive, Columbus, Ohio           to Registrant's Annual Report on Form 10-K for
                                                                      the fiscal year ended June 30, 1998
 
        10(d)      Third Lease Amendment to office located at 2800    Incorporated herein by reference to Exhibit 10(c)
                   Corporate Exchange Drive, Columbus, Ohio           to Registrant's Annual Report on Form 10-K for
                                                                      the fiscal year ended June 30, 1994
 
        10(e)      Fourth Lease Amendment to office located at 2800   Incorporated herein by reference to Exhibit 10(e)
                   Corporate Exchange Drive, Columbus, Ohio           to Registrant's Annual Report on Form 10-K for
                                                                      the fiscal year ended June 30, 1998
 
        10(f)      Fifth Lease Amendment to office located at 2800    Incorporated herein by reference to Exhibit 10(f)
                   Corporate Exchange Drive, Columbus, Ohio           to Registrant's Annual Report on Form 10-K for
                                                                      the fiscal year ended June 30, 1998
 
        10(g)      Progress Software Application Partner Agreement    Incorporated herein by reference to Exhibit 10(e)
                   dated February 8, 1995                             to Registrant's Quarterly Report on Form 10-Q for
                                                                      fiscal quarter ended March 31, 1995
 
        10(h)      Amendment to Progress Software Application         Incorporated herein by reference to Exhibit 10(h)
                   Partner Agreement dated July 1, 1997               to Registrant's Annual Report on Form 10-K for
                                                                      the fiscal year ended June 30, 1998
 
        10(i)      Second Amendment to Progress Software Application  Incorporated herein by reference to Exhibit 10(i)
                   Partner Agreement dated July 1, 1998               to Registrant's Annual Report on Form 10-K for
                                                                      the fiscal year ended June 30, 1998
 
        10(j)*     Summary of Bonus Plan                              Incorporated herein by reference to Exhibit 10(j)
                                                                      to Registrant's Annual Report on Form 10-K for
                                                                      the fiscal year ended June 30, 1998
 
        10(k)*     Symix Systems, Inc. Stock Option Plan for Outside  Incorporated herein by reference to Exhibit 10(i)
                   Directors                                          of Registrant's Annual Report on Form 10-K for
                                                                      fiscal year ended June 30, 1993
 
        10(l)*     Symix Systems, Inc. Non-Qualified Stock Option     Incorporated herein by reference to Exhibit 10(a)
                   Plan for Key Executives                            to Registrant's Quarterly Report on Form 10-Q for
                                                                      fiscal quarter ended March 31, 1996
 
        10(m)*     Symix Systems, Inc. Non-Qualified Stock Option     Incorporated herein by reference to Exhibit 10(a)
                   Plan for Key Employees, as amended                 to Registrant's Annual Report on Form 10-K for
                                                                      the fiscal year ended June 30, 1993
 
        10(n)*     Symix Systems, Inc. Non-Qualified Stock Option     Incorporated herein by reference to Exhibit 10(a)
                   Plan for Key Executives                            to Registrant's Quarterly Report on Form 10-Q for
                                                                      the fiscal quarter ended March 31, 1996
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   EXHIBIT NO.                        DESCRIPTION                                           PAGE
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<C>                <S>                                                <C>
        10(o)*     Symix Systems, Inc. Stock Option Plan for Outside  Incorporated herein by reference to Exhibit 10(i)
                   Directors                                          to Registrant's Annual Report on Form 10-K for
                                                                      fiscal year ended June 30, 1993
 
        10(p)*     Sasser Employment Agreement                        Incorporated herein by reference to Exhibit 10(b)
                                                                      to Registrant's Quarterly Report on Form 10-Q for
                                                                      fiscal quarter ended March 31, 1996
 
        10(q)*     Stock Option Agreement between the Company and     Incorporated herein by reference to Exhibit 10(c)
                   Stephen A. Sasser dated January 17, 1996           to Registrant's Quarterly Report on Form 10-Q for
                                                                      fiscal quarter ended March 31, 1996
 
        10(r)      Loan Agreement among Symix Systems, Inc., Symix    Incorporated herein by reference to Exhibit
                   Computer Systems, Inc. and Bank One, Columbus,     10(a)(1) to Registrant's Form 10-Q for fiscal
                   N.A. dated May 20, 1996                            quarter ended September 30, 1997
 
        10(s)      First Amendment to Loan Agreement among Symix      Incorporated herein by reference to Exhibit 10(b)
                   Systems, Inc., Symix Computer Systems, Inc. and    to Registrant's Form 10-Q for fiscal quarter
                   Bank One, Columbus, N.A.                           ended September 30, 1997
 
        10(t)      Second Amendment to Loan Agreement Among Symix     Incorporated herein by reference to Exhibit 10(b)
                   Systems, Inc., Symix Computer Systems, Inc. and    to Registrant's Form 10-Q for fiscal quarter
                   Bank One, NA                                       ended March 31, 1998
 
        10(u)      Third Amendment to Loan Agreement Among Symix      Incorporated herein by reference to Exhibit 10(u)
                   Systems, Inc., Symix Computer Systems, Inc. and    to Registrant's Annual Report on Form 10-K for
                   Bank One, NA                                       the fiscal year ended June 30, 1998
 
        21         Subsidiaries of the Registrant                     Filed herein
 
        23         Consent of Independent Auditors                    Incorporated herein by reference to Exhibit 23 to
                                                                      Registrant's Annual Report on Form 10-K for the
                                                                      fiscal year ended June 30, 1998
 
        24         Powers of Attorney                                 Incorporated herein by reference to Exhibit 24 to
                                                                      Registrant's Annual Report on Form 10-K for the
                                                                      fiscal year ended June 30, 1998
 
        27         Financial Data Schedule                            Incorporated herein by reference to Exhibit 27 to
                                                                      Registrant's Annual Report on Form 10-K for the
                                                                      fiscal year ended June 30, 1998
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*Indicates management contracts or compensatory plans or arrangements that are
 required to be filed as an exhibit for the fiscal year ended June 30, 1998
 
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