
Fix OneDrive Sync Error 0x8004de40 – Authentication Failure
You're working on a file when OneDrive pops up an error: "Authentication failed – Error c...

You're working on a file when OneDrive pops up an error: "Authentication failed – Error c...

You see a message that Windows Defender definitions are out of sync, or that the client and serve...

You see a message that your OneDrive sync is paused or not working due to an invalid configuratio...

After a Windows or Microsoft 365 update, OneDrive may get stuck on the sign-in screen or show err...

If Windows Search stops returning results, takes too long, or shows errors, resetting the search ...

You try to map a network drive in PowerShell, but get 'access denied'. This is common when permis...