Lionelbain

The question mentioned above is thus definite in such a case.

If the folder size is initially lower than 4 GB but then grows to above 4 GB over time, you will not see this problem through normal folder synchronization.

Make sure outlook is closed and rename the folder to something else - Outlook-bad is usually enough.

If your account is compromised or hacked, use Microsoft’s sign-in helper to recover your account and reset your security settings.