Fix Microsoft Teams Error caa70004 (Login Loop)

Updated: 12/1/2025

You have a meeting starting in 2 minutes. You open Teams, but instead of your calendar, you get a white screen or the message: 'We run into a problem. Restarting isn't going to help. Error code: caa70004'. This error typically means the desktop client is trying to log you in with an expired security token stored in your local cache, or it is conflicting with your Windows account manager.

Table of Contents

Method 1: The Deep Cache Cleanse

Signing out is not enough. Teams stores thousands of temporary files that get corrupted over time. You must delete them manually.

Step 1: Quit Teams

Right-click the Teams icon in your system tray (near the clock) and select Quit. Closing the window is not enough.

Step 2: Delete Cache Files

Press Win + R and paste this command:

%appdata%\Microsoft\Teams

Delete everything inside this folder. It is safe; Teams will re-download your chat history from the cloud when you restart.

Method 2: Enable TLS 1.2

Teams requires specific internet security protocols to connect to Microsoft servers. If disabled, the handshake fails.

Step 1: Internet Options

Press Win + R, type inetcpl.cpl, and hit Enter.

Step 2: Advanced Tab

Go to the Advanced tab. Scroll down to the 'Security' section. Ensure that Use TLS 1.1 and Use TLS 1.2 are CHECKED. Uncheck SSL 3.0.

Method 3: Run in Compatibility Mode

If Windows updates broke the app, force it to run as an older version.

  • Right-click the Teams shortcut > Properties.
  • Go to the Compatibility tab.
  • Check 'Run this program in compatibility mode for' and select Windows 8.
  • Click Apply and Restart.