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                       SECURITIES AND EXCHANGE COMMISSION
                            WASHINGTON, D. C. 20549

                       ---------------------------------

                                  FORM 10-K/A
                                   AMENDMENT
                       ----------------------------------


            TO ANNUAL AND TRANSITION REPORTS PURSUANT TO SECTIONS 13

                OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

[X]  ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE
     ACT OF 1934

                   For the fiscal year ended December 31, 1999

[ ]  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: 0-26298
                              HARBINGER CORPORATION
               (Exact Name of Registrant Specified in Its Charter)

              GEORGIA                                  58-1817306
   (State or Other Jurisdiction of         (I.R.S. Employer Identification No.)
    Incorporation or Organization)
      1277 LENOX PARK BOULEVARD                           30319
         ATLANTA, GEORGIA                               (Zip Code)
(Address of Principal Executive Office)

       REGISTRANT'S TELEPHONE NUMBER, INCLUDING AREA CODE: (404) 467-3000

                        ---------------------------------

                 Securities registered pursuant to Section 12(b) of the Act:
                                      None

                        ---------------------------------

           Securities registered pursuant to Section 12(g) of the Act:

          Title of Each Class              Name of Exchange on Which Registered
          -------------------              ------------------------------------
Common Stock, par value $.0001 per share        The Nasdaq National Market

     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 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. [X]

     The aggregate market value of the voting stock held by non-affiliates of
the Registrant, based upon the average of the closing bid and ask quotations for
the Common Stock on March 8, 2000 as reported by The Nasdaq Stock Market, was
approximately $977,432,495. The shares of Common Stock held by each officer and
director and by each person known to the Registrant who owns 5% or more of the
outstanding Common Stock have been excluded in that such persons may be deemed
to be affiliates. This determination of affiliate status is not necessarily a
conclusive determination for other purposes. As of March 8, 2000, Registrant had
outstanding approximately 39,594,515 shares of Common Stock.

                       DOCUMENTS INCORPORATED BY REFERENCE

The Registrant's definitive Proxy Statement for the Annual Meeting of
Shareholders to be held April 25, 2000 is incorporated by reference in Part III
of this Form 10-K to the extent stated herein.


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ITEM 14. EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

     This Amendment to Form 10-K is submitted for the purpose of filing certain
exhibits noted below.

<TABLE>
<CAPTION>

EXHIBIT NUMBER                          DESCRIPTION
--------------                          -----------

    <S>        <C>
    10.1       Employment Agreement between the Company and Mr. James M. Travers
               effective as of January 19, 2000.

    10.9       Amended and Restated 1993 Stock Option Plan for Nonemployee
               Directors.

    10.10      Harbinger Corporation 1996 Stock Option Plan.

    10.11      Amended and Restated Harbinger Corporation Employee Stock
               Purchase Plan.
</TABLE>


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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 31st day of
March, 1999.

                                         HARBINGER CORPORATION



                                         By: /s/ James M. Travers
                                             ------------------------------
                                             James M. Travers
                                             President  and Chief Executive
                                             Officer


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     Pursuant to the requirements of the Securities Exchange Act of 1934, this
report has been signed below by the following persons on behalf of the
Registrant in the capacities and on the dates indicated.

<TABLE>
<CAPTION>

      SIGNATURE                        TITLE                         DATE
      ---------                        -----                         ----

<S>                           <C>                               <C>
 /s/ James M. Travers         Chief Executive Officer;          March 31, 2000
 --------------------------   President; Director
 James M. Travers


 /s/ David T. Leach           Vice Chairman; Director           March 31, 2000
 ------------------------
 David T. Leach


 /s/ James K. McCormick       Chief Financial Officer;          March 31, 2000
 ------------------------     (Principal Financial Officer;
 James K. McCormick           Principal Accounting Officer)


 /s/ William D. Savoy         Director                          March 31, 2000
 ------------------------
 William D. Savoy


                              Director                          March __, 2000
 ------------------------
 William B. King


 /s/ Stuart L. Bell           Director                          March 31, 2000
 ------------------------
 Stuart L. Bell


 /s/ Benn R. Konsynski        Director                          March 31, 2000
 ------------------------
 Benn R. Konsynski


 /s/ Ad Nederlof              Director                          March 31, 2000
 ------------------------
 Ad Nederlof


                              Director                          March __, 2000
 ------------------------
 Klaus Neugebauer


 /s/ David Hildes             Director                          March 31, 2000
 ------------------------
 David Hildes


 /s/ John Lowenberg           Director                          March 31, 2000
 ------------------------
 John Lowenberg
</TABLE>