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                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                               WASHINGTON DC 20549

                                   FORM 10-K/A

                         (Amendment No. 1 to Form 10-K)

                  ANNUAL REPORT PURSUANT TO SECTION 13 or 15(d)
                     OF THE SECURITIES EXCHANGE ACT OF 1934

For the year ended December 31, 2001              Commission file number 0-26376

                            ON TECHNOLOGY CORPORATION
             (Exact name of registrant as specified in its charter)

        Delaware                                        04-3162846
 (State or incorporation)                   (IRS Employer Identification Number)

                          880 Winter Street, Building 4
                        Waltham, Massachusetts 02451-1449
                                 (781) 487-3300
             (Address and telephone of principal executive offices)

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

Securities registered pursuant to Section 12(g) of the Act: Common Stock,
par value $0.01 per share

Indicate by check mark whether 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. [ ]

The aggregate market value of voting stock held by nonaffiliates of the
registrant was $41,635,903, as of March 13, 2002.

The number of shares of Common Stock, $0.01 par value, outstanding as of March
13, 2002 was 23,030,593

DOCUMENTS INCORPORATED BY REFERENCE

The information required by Part III of this Annual Report on Form 10-K, to the
extent not set forth herein, is incorporated by reference from specified
portions of the Registrant's definitive Proxy Statement for the 2002 Annual
Meeting of Stockholders scheduled for May 16, 2002.

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                                Explanatory Note

The sole purpose of this Amendment No. 1 is to correct the inadvertent omission
of the signature page from the electronic transmission of the Annual Report on
Form 10-K as originally filed on March 26, 2002 (the "Original Filing"). The
omitted signature page follows on the next page.

Any items in the Original Filing not expressly changed hereby shall be as set
forth in the Original Filing. All information contained in this amendment and
the Original Filing is subject to updating and supplementing as provided in the
Company's periodic reports filed with the SEC subsequent to the date of such
reports.

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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 TECHNOLOGY CORPORATION



                                      /s/ Robert L. Doretti
                                      ---------------------------------------
Date: March 26, 2002                  Name:    Robert L. Doretti
                                      Title:   Chairman, President
                                               and Chief Executive Officer

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 and
in the capacities and the dates indicated.

                                     /s/ Steven R. Wasserman
                                     ----------------------------------------
Date: March 26, 2002                 Name:    Steven R. Wasserman
                                     Title:   Vice President of Finance
                                              and Chief Financial Officer

                                     /s/ Robert P. Badavas
                                     ----------------------------------------
Date: March 26, 2002                 Name:    Robert P. Badavas
                                     Title:   Director


                                     /s/ John Cassarini
                                     ----------------------------------------
Date: March 26, 2002                 Name:    John Cassarini
                                     Title:   Director


                                     /s/ Paul C. O'Brien
                                     ----------------------------------------
Date: March 26, 2002                 Name:    Paul C. O'Brien
                                     Title:   Director


                                     /s/ Louis J. Rupnik
                                     ----------------------------------------
Date: March 26, 2002                 Name:    Louis J. Rupnik
                                     Title:   Director


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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 Amendment No. 1 to Annual
Report on Form 10-K to be signed on its behalf by the undersigned, thereunto
duly authorized.

                                     ON TECHNOLOGY CORPORATION



                                     /s/ Steven R. Wasserman
                                     ------------------------------
Date: April 1, 2002                  Name:   Steven R. Wasserman
                                     Title:  Vice President of Finance
                                             and Chief Financial Officer