Lost events when took off outlook calendar

Deleted Outlook calendar events can sometimes be recovered, depending on how they were removed and which Outlook experience is in use.

1. Check Deleted Items and Recoverable Items
   • In Outlook on the web or Outlook.com, open the Deleted Items folder and look for deleted calendar items.
   • If they are not there, use the Recoverable Items folder:
     1. In the left pane, select the Deleted Items folder.
     2. At the top of the message list, select Recover items deleted from this folder.
     3. Select the calendar items to restore and choose Restore.
   • Restored calendar items are returned to the calendar. If the original calendar no longer exists, they are restored to the default calendar.
2. If events were removed because of a shared calendar issue
   • There was a known issue in some Outlook for Mac REST calendars where removing a shared/delegated calendar with edit permissions could delete events from the owner’s calendar and they could not be recovered.
   • This issue is fixed in newer builds (16.23.1 and later). If the data loss was caused by that scenario and occurred before updating, there is no built‑in way to restore those events; recovery would then depend on backups.

If the deleted events do not appear in Deleted Items or the Recoverable Items folder, they may have been permanently removed and cannot be restored via Outlook’s built‑in recovery features.

References:

• Recover and restore deleted items in Outlook
• If a shared calendar is removed, events may get deleted on the owner's calendar