MacOS – Exchange Calendar syncing issue on Maverics

calendarexchangemacos

I have an Exchange calendar synced with Mavericks' Calendar app. I've changed time of one event. Since that a window with following message appears over and over:

Calendar can’t delete an occurrence from the repeating the event
“[event]” from the Exchange server.

I've tried to re-add the calendar as well as the whole Exchange account. Deleting the Calendar Cache* files (in ~/Library/Calendars) screws up all calendar data and I'm not able to re-add the synced calendars.

I've all calendars synced in cloud (iCloud, Google, Exchange), so deleting the Calendar files is no issue.

Best Answer

After trial and error, these actions finally solved this issue:

  1. Delete Exchange account from Internet Accounts in System Settings
  2. Clean User and System cache with Onyx
  3. Restart Computer
  4. Re-add the Exchange account

Tested on MacOS 10.9.4.