Quick Answer
Fix token expiration: sync your system time, clear the token cache in Windows Credential Manager, then sign out and back into the app. If the error persists, reset the app through Settings > Apps & features.
Why This Happens
I know this error is infuriating. You’re working, and suddenly the app tells you Authentication failure – token expired. It’s not your fault. Tokens have a built-in lifespan. Microsoft’s Azure AD, for example, sets them to 24 hours by default. But the real trigger is often simpler: your computer’s clock is off. Even a 5-minute drift can break the token validation. I’ve seen this happen after a daylight saving change or when a cheap motherboard battery dies. The app can’t refresh the token if the time between your system and the server don’t match.
Fix Steps – Do This First
These steps work for most authentication failures on Windows 10/11, Office 365, Outlook, and web browsers. Skip nothing.
- Sync your system time. Right-click the clock on your taskbar > Adjust date/time. Turn on Set time automatically and Set time zone automatically. Hit Sync now. Wait 10 seconds.
- Open Windows Credential Manager. Press Win + R, type
control /name Microsoft.CredentialManager, and hit Enter. Click Windows Credentials. - Delete old tokens. Look for any entry with “MicrosoftOffice”, “Outlook”, “Azure”, or the app’s name like “Teams” or “VPN”. Click the arrow to expand, then Remove. Confirm.
- Sign out of the app. If it’s a browser, clear cookies for the site. If it’s a desktop app, go to File > Account (in Office) or the profile icon > Sign Out.
- Sign back in. Authenticate again. The app will ask for a fresh token. Should work now.
If That Doesn’t Work
Sometimes the token is stuck deeper. Here’s the backup plan:
- Reset the app. Go to Settings > Apps > Apps & features. Find the app, click Advanced options, then Reset. This wipes the app’s local data and token cache. You won’t lose files, but you’ll need to log in again.
- Check proxy or VPN. If you use a proxy or VPN, it might block token refresh. Turn it off temporarily. If the error goes away, your proxy is the problem – whitelist the app’s endpoints (like login.microsoftonline.com for MS products).
- Reinstall the app. Last resort. Uninstall, reboot, then install fresh. This clears everything, including corrupted token files.
Prevention Tips
I hate seeing the same error twice. Here’s how to avoid it:
| Issue | Fix |
|---|---|
| System time out of sync | Enable automatic time sync in Windows. Check it monthly. |
| Token expiration mid-session | Modern apps (like Teams, Outlook) refresh tokens silently. If yours doesn’t, update the app. Old versions are lazy. |
| Multiple accounts on one device | Use only one work account per app. Token conflicts happen. |
One more thing: if you use Azure AD, ask your admin to extend token lifetime from 24 hours to 7 days. It’s done via Conditional Access policies. That saved my team a bunch of calls.
I had a user with this error on Windows 10 after a daylight saving change. 7 minutes off the time. Synced it, cleared credentials, and it worked instantly. Don't overthink it – time is usually the culprit.