Error logging into Teams

EZ235 1 Reputation point
2021-08-21T01:56:44.217+00:00

Sorry, but we’re having trouble signing you in.

AADSTS50020: User account 'username@Stuff .com' from identity provider 'live.com' does not exist in tenant 'Microsoft Services' and cannot access the application '1fec8e78-bce4-4aaf-ab1b-5451cc387264'(Microsoft Teams) in that tenant. The account needs to be added as an external user in the tenant first. Sign out and sign in again with a different Azure Active Directory user account.
Request Id: 347a57b3-9f1a-4c4d-8312-0466d9b30100
Correlation Id: 0fac2e8e-e14d-450c-9b5d-7d892de31532
Timestamp: 2021-08-21T01:55:07Z
Message: AADSTS50020: User account 'username@Stuff .com' from identity provider 'live.com' does not exist in tenant 'Microsoft Services' and cannot access the application '1fec8e78-bce4-4aaf-ab1b-5451cc387264'(Microsoft Teams) in that tenant. The account needs to be added as an external user in the tenant first. Sign out and sign in again with a different Azure Active Directory user account.
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Microsoft Teams
Microsoft Teams
A Microsoft customizable chat-based workspace.
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  1. JimmyYang-MSFT 49,286 Reputation points Microsoft Vendor
    2021-08-23T06:02:19.957+00:00

    Hi @EZ235

    According to your error message, it seems that the error message is a Azure AD login error. This article give a explanation of the issue: .

    In this case, it recommends you delete your Teams client cache as the following steps:

    1. Fully exit the Microsoft Teams desktop client. To do this, either right click Teams from the Icon Tray and select ‘Quit’. Or run Task Manager and fully kill the process.
    2. Go to File Explorer, and type in %appdata%\Microsoft\teams.
    3. Once in the directory, delete any file in the following folders:
      %appdata%\Microsoft\teams\application cache\cache
      %appdata%\Microsoft\teams\blob_storage
      %appdata%\Microsoft\teams\Cache
      %appdata%\Microsoft\teams\databases
      %appdata%\Microsoft\teams\GPUcache
      %appdata%\Microsoft\teams\IndexedDB
      %appdata%\Microsoft\teams\Local Storage
      %appdata%\Microsoft\teams\tmp

    If it is no luck after that, you could uninstall and reinstall the Microsoft Teams client and have a try.

    Note: Microsoft is providing this information as a convenience to you. The sites are not controlled by Microsoft. Microsoft cannot make any representations regarding the quality, safety, or suitability of any software or information found there. Please make sure that you completely understand the risk before retrieving any suggestions from the above link.