copilot chats not avalible

The “This chat cannot be opened” message doesn’t necessarily mean your conversations have been deleted. Since all of them stopped opening after the update, first check whether the problem is with the app or with access to your account’s chat history.

Try Copilot in a browser using the same Microsoft account. For personal Copilot, use https://copilot.microsoft.com/; for work or school, open Microsoft 365 Copilot through your organisation’s account. Make sure you haven’t switched between a personal and work account with the same email address.

If the chats open in the browser, use that temporarily, then sign out of the affected app, fully close it, and sign back in. If you’re already using the browser, try a private window to test with a fresh session.

If the same chats fail in both places, reinstalling the app is unlikely to help. Report it through Copilot’s Help/Feedback option, including the exact error, app version, and when it started. 

Avoid deleting the affected conversations while troubleshooting—you may still be able to regain access once the underlying issue is resolved.