Fix Microsoft Teams Sign-In Loop: Clear Cache and Repair Device Registration
Teams keeps asking you to sign in, shows a blank window, or says it could not sign you in? Clear the cache, check the Entra token and fix clock skew.
Common Symptoms and Quick Fixes
| Symptom | Likely Cause | Quick Fix |
|---|---|---|
| Endless sign-in loop | Corrupted cached tokens | Clear the Teams cache |
| Blank white window on launch | Damaged local cache or WebView2 | Clear cache; repair or reset the app |
| Could not sign you in | No Primary Refresh Token or wrong clock | Check dsregcmd status; resync time |
Method 1: Quit Teams and Clear the Cache
Run in Command Prompt. The first block is for the new Teams, the second for classic Teams. Your chats live in the cloud and are not deleted.
taskkill /F /IM ms-teams.exe
rmdir /S /Q "%LOCALAPPDATA%\Packages\MSTeams_8wekyb3d8bbwe\LocalCache"
:: Classic Teams
taskkill /F /IM Teams.exe
rmdir /S /Q "%APPDATA%\Microsoft\Teams"Method 2: Check Device Registration and the Entra Token
Run this and look for AzureAdJoined and AzureAdPrt.
dsregcmd /status1
Read the resultAzureAdPrt : YES means the token is healthy. If it says NO, sign out of Windows and back in, then re-test.
2
Still NOCheck Event Viewer > Applications and Services Logs > Microsoft > Windows > AAD for errors, and confirm the PC can reach login.microsoftonline.com.
Method 3: Resync the System Clock
Sign-in tokens fail when the clock is more than a few minutes off.
w32tm /resyncPro Tip for AdministratorsOn domain PCs, make sure the domain controller time source is correct, otherwise every client drifts.
Method 4: Repair or Reset the App
Settings > Apps > Installed apps > Microsoft Teams > Advanced options. Click Repair first. If it still fails, click Reset and sign in again.
Frequently Asked Questions (FAQ)
Q: Will clearing the cache remove my chats or files?
No. Chats, files and meetings are stored in Microsoft 365, not in the local cache.
Q: Do I still need classic Teams?
No. Classic Teams is retired; use the new Teams app.