Shared Calendars No Longer Visible

Hey Lizzie — because the calendars vanished on Android, desktop, and the web at the same time, this is unlikely to be a local cache problem. I’d repair the sharing relationship at the source account.

On the calendar owner’s account in Outlook on the web, open Settings > Calendar > Shared calendars, remove the affected recipient, save, and share it again. On the recipient account, remove any stale copy under People’s calendars, accept the new invitation from the email, and then sign out/in on the other clients. First make sure the owner still sees the original events before removing anything—do not delete the calendar itself.

If a fresh invitation also fails in Outlook on the web, that points to a Microsoft account/service-side permissions issue. In that case contact Microsoft Support with the owner/recipient addresses, approximate failure date, and the web reproduction; reinstalling every client will not repair a server-side share.