Resolve sign-in errors in Teams

If your users encounter errors when they try to sign in to Microsoft Teams, use the following steps to troubleshoot the problem.

Run the Teams Sign-in diagnostic

1. Select the following button to populate the diagnostic in the Microsoft 365 admin center:

   Run Tests: Teams Sign-in

2. In the Provide the username or email of the user reporting this issue field, enter the email address of the affected user, and then select Run Tests.

Run the Microsoft Remote Connectivity Analyzer diagnostic

1. Open a web browser, and then go to the Teams Sign in test.
2. Sign in by using the credentials of the user account that you want to test.
3. Enter the provided verification code.
4. Select Verify.

This test verifies that the user account meets the requirements to sign in to Teams.

Use Microsoft Support and Recovery Assistant

If the diagnostic doesn't detect any issue, but you still can't sign in to Teams, or you don't have a Microsoft 365 administrator account, select the following button to download the Assistant and automatically start the tests. For more information about the tool, see About Microsoft Support and Recovery Assistant.

Fix the issue manually

If you want to perform the checks and fix the issue manually, follow these steps:

1. If the diagnostic detects an issue that affects the instance of Teams on the tenant, follow the provided solution to fix the issue. If the diagnostic doesn't detect an issue, check whether the user's Teams client is running the latest update. Select the Settings and more menu next to the user's profile picture at the top right of the Teams window, and then select Check for updates.

The desktop app is configured to update automatically. However, if you find that the app is missing the latest update, follow the instructions to install it, and try again to sign in. If you still see an error when you try to sign in to Teams, go to step 3.

1. If you use a federated sign-in provider such as Active Directory Federation Services (AD FS), verify the AD FS sign-in configuration by using the Microsoft 365 Single Sign-on Test in the Microsoft Remote Connectivity Analyzer.

2. Check the error code on the Teams sign-in screen. If the code is listed here, follow the provided guidance to fix the error. If the code isn't listed here, see Why am I having trouble signing in to Microsoft Teams?

   • 0xCAA82EE7 or 0xCAA82EE2
     Make sure that the user has Internet access. Then, use the Network assessment tool to verify that the network and network elements between the user location and the Microsoft network are configured correctly. This is necessary to enable communication to the IP addresses and ports that are required for Teams calls.

     For information about endpoints that users should be able to reach if they're using Teams in Microsoft 365 plans, government environments, or other clouds, see Microsoft 365 URLs and IP address ranges.

   • 0xCAA20004
     This error occurs if an issue affects conditional access. For more information, see Conditional Access policies for Teams.

   • 0xCAA70004 or 0xCAA70007, or if the sign-in issue also occurs in other Office applications: See Connection issues in sign-in after update to Office 2016 build 16.0.7967.

3. If the sign-in error occurs only in the Teams web client, see Microsoft Teams is stuck in a login loop for resolutions that are specific to the user's preferred browser.

4. If the error persists, reinstall Teams as follows:

   1. Uninstall Teams.
   2. Browse to the %appdata%\Microsoft folder on the user's computer, and delete the Teams folder.
   3. Download and install Teams. If possible, reinstall Teams as an administrator. To do this, right-click the Teams installer file, and select Run as administrator.

If none of these steps helps to resolve the Teams sign-in issue, create a support request. For the request, collect debug logs, and provide the error code that's displayed on the Teams sign-in screen.