How do I fix this microsoft 365 copilot error message "Sorry, we ran into a problem loading this app"?

Hi Daniel,

Thank you for reaching out and sharing your experience with the Microsoft Community.

I completely understand how frustrating it can be to run into this kind of issue - especially after trying all the right steps like repairing, resetting, reinstalling, and even disabling it from startup.

The additional message you mentioned, “HTTP ERROR 401 – This page isn’t working right now,” typically points to an authentication issue, where the app is unable to verify your credentials or access the necessary services.

Here are a few suggestions that might help:

1. Check Your Internet Connection Ensure your network is stable and not blocking Microsoft services (especially if you're using a VPN or firewall).
2. Sign Out and Sign Back In Open any Office app, go to your profile in the top-right corner, sign out, and then sign back in using the account linked to your subscription.
3. Clear Cached Credentials Use the Windows Credential Manager to remove any saved Microsoft 365 credentials and try signing in again.
4. Run Office as Administrator Right-click the Office app and choose “Run as administrator” to ensure it has the necessary permissions.
5. Check for Windows Updates Make sure your system is fully updated by going to Settings > Windows Update.

If things still don’t work out, feel free to share an update, I’ll be happy to assist further.

Wishing you the best of luck!

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