Microsoft Teams Keeps Asking You to Sign In or Gets Stuck on the Loading Screen

You open Microsoft Teams and it either spins forever on the loading screen, or it accepts your password and then bounces you straight back to the sign-in box — over and over.

Why: This is almost never a wrong password (a wrong password locks you out, it doesn’t loop). It’s usually a stale local cache, a blocked connection (often a VPN or a corporate firewall), or an incorrect date/time on the PC that breaks the secure connection Teams needs to authenticate. Microsoft’s own sign-in troubleshooting flags an incorrect clock as status code 0xCAA20003 and a blocked connection as 0xCAA70007 / 0xCAA82EE2.

Fix 1: Quit Teams completely and check the basics

The loading screen often clears with a true restart (not just closing the window):

1. In the notification area (system tray, bottom-right), right-click the Teams icon and select Quit. Closing the window alone leaves Teams running.
2. Confirm your PC’s clock is right: Settings → Time & language → Date & time and turn on Set time automatically. A wrong clock blocks the secure (HTTPS) sign-in.
3. Open a browser and load any website to confirm the internet works.
4. If you’re on a VPN, turn it off and back on (or disconnect entirely) and reopen Teams. VPNs and strict firewalls frequently block the sign-in endpoints.
5. Reopen Teams.

Fix 2: Sign in to Teams on the web to isolate the problem

This tells you instantly whether the issue is the desktop app or your account:

1. Go to https://teams.microsoft.com/ in your browser and sign in.
2. If the web version works, the problem is the desktop app’s cache — go to Fix 3.
3. If the web version also loops, note the status code on screen and send it to your IT admin; sign-in policy issues can only be cleared on their end.

Fix 3: Clear the Teams cache

A corrupted cache is the most common cause of both the login loop and the endless spinner. The path differs between the two versions of Teams.

New Teams (the default app on current Windows):

1. Right-click the Teams icon on the taskbar and select Quit.
2. Press Windows key + R, paste this path, and press Enter: %userprofile%\appdata\local\Packages\MSTeams_8wekyb3d8bbwe\LocalCache\Microsoft\MSTeams
3. Delete everything inside that folder.
4. Restart Teams and sign in. The first launch is slower while the cache rebuilds.

You can also reset new Teams without touching files: Settings → Apps → Installed apps → Microsoft Teams → … (More options) → Advanced options → Reset. (This wipes your local personalization but keeps your account data.)

Classic Teams (work or school):

1. Right-click the Teams icon and select Quit.
2. Press Windows key + R, paste %appdata%\Microsoft\Teams, and press Enter.
3. Delete all files and folders inside, then restart Teams.

FAQ

How do I know if I have “new Teams” or “classic Teams”? New Teams is the standard app on up-to-date Windows 11 and most Windows 10 machines now; it lives under the MSTeams_8wekyb3d8bbwe package folder. Classic Teams uses the %appdata%\Microsoft\Teams folder. If unsure, check both — only one will exist.

Will clearing the cache delete my chats or files? No. Your messages, files, and channels live in the cloud. Clearing the cache only removes the local copy, which is rebuilt on next launch.

It loops only on one PC. That PC has the bad cache or a blocked connection (VPN/firewall/clock). A second device signing in fine confirms your account is healthy.

Sources: Microsoft Support — Why am I having trouble signing in to Microsoft Teams? · Microsoft Learn — Clear the Teams client cache