Microsoft Teams keeps asking me to sign in every 20 minutes

Quit Teams completely and clear its local cache; if the prompt still returns every 20 minutes—especially in Teams on the web or another device—ask your IT administrator to check the Microsoft Entra sign-in-frequency policies applied to your account.

1. Clear the Teams cache

Windows

1. Right-click the Microsoft Teams icon in the taskbar notification area and select Quit.
2. Open File Explorer.
3. Enter this path in the address bar:

      %appdata%\Microsoft\Teams
   

4. Delete the contents of that folder.
5. Start Teams and sign in again.

macOS

1. Quit Teams.
2. In Finder, select Go > Go to Folder.
3. Enter:

      ~/Library/Application Support/Microsoft/Teams
   

4. Delete that directory, restart Teams, and sign in.

Clearing the cache does not uninstall Teams, but it removes locally cached web data, icons, thumbnails, local message history, display images, and add-ons.^1^

If this resolves the issue permanently, the local client cache was involved. If it resumes on the same regular 20-minute interval, proceed below rather than repeatedly clearing the cache.

2. Determine whether an organizational policy is forcing the prompts

Open Teams on the web and use it for longer than 20 minutes. Also note whether Outlook, OneDrive, or Teams on another device asks you to authenticate at a similar interval.

• Only the desktop app is affected: uninstall and reinstall Teams, which is Microsoft’s next documented client-recovery option.^1^
• The web client or multiple devices are also affected: this points away from a local cache problem. Microsoft Entra Conditional Access can define how long users remain signed in, and the Teams web client follows that sign-in-frequency setting.^2^

The default Entra behavior is a rolling 90-day window when the session’s security posture has not changed, so a consistent 20-minute prompt is not normal default behavior.^2^

3. What your Microsoft 365 administrator should check

Send the administrator:

• Your username
• The approximate timestamps of several prompts
• Whether Teams desktop, Teams web, or other devices are affected
• Any status or error code shown in the lower-left corner of the sign-in window

Microsoft notes that the status code helps administrators diagnose Teams sign-in failures and that many authentication problems require administrator action.^3^

An administrator with at least the Conditional Access Administrator role should review the policies applying to the user under:

1. Microsoft Entra admin center
2. Entra ID > Conditional Access > Policies
3. Open the applicable policy.
4. Check Access controls > Session > Sign-in frequency.
5. Determine whether it uses an unusually short periodic interval or Every time.
6. Test any proposed change before production rollout and retain stricter settings where the organization’s security requirements need them.^4^

Reauthentication settings can apply to both the first authentication factor and MFA. Microsoft recommends managing these requirements through the Sign-in frequency policy when session restrictions are needed.^5^

If no applicable policy explains the prompts, the Microsoft 365 administrator should use the collected timestamps and status code to examine the account’s sign-in activity or open a Microsoft support request.

References

1. I can't reconnect to Microsoft Teams | Microsoft Support
2. Conditional Access adaptive session lifetime policies
3. Why am I having trouble signing in to Microsoft Teams? | Microsoft Support
4. Configure adaptive session lifetime policies
5. Reauthentication prompts and session lifetime for Microsoft Entra multifactor authentication