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                                                                   EXHIBIT 10.50

Letter Agreement dated September 11, 2000 between Medical Manager Corporation
and Marvin P. Rich




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                           MEDICAL MANAGER CORPORATION
                            669 RIVER DRIVE, CENTER 2
                       ELMWOOD PARK, NEW JERSEY 07407-1361


                                                              September 11, 2000


Mr. Marvin P. Rich
c/o Medical Manager Corporation
669 River Drive, Center 2
Elmwood Park, New Jersey  07407-1361

Dear Marv:

         Reference is made to the Amended and Restated Employment Agreement
dated as of June 18, 2000 (the "Employment Agreement"), by and between Medical
Manager Corporation, a Delaware corporation, CareInsite, Inc., a Delaware
corporation, and you.

         The first sentence of Section 5.3(a)(iv) of the Employment Agreement is
hereby amended to delete the words "and remain exercisable until the first
anniversary of the date of termination" and replace them with "and remain
exercisable until such options would otherwise expire under the terms thereof".

         The foregoing amendment to the Employment Agreement shall be effective
as of the date hereof. All other provisions of the Employment Agreement shall
continue in full force and effect.

                                    MEDICAL MANAGER CORPORATION

                                    By:      /s/ Charles Mele
                                       -----------------------------------------
                                             Name:  Charles A. Mele
                                             Title: Executive Vice President -
                                                    General Counsel

Accepted and Agreed:


/s/ Marvin P. Rich                  CAREINSITE, INC.
- ---------------------------
Marvin P. Rich

                                    By:      /s/ David C. Amburgey
                                       -----------------------------------------
                                             Name:  David C. Amburgey
                                             Title: SVP - General Counsel