Hi @Humphreys, Oliver (EPLWG)
Based on your description, you can try to sign in to Teams online using a browser like Chrome or Edge and see if you can access your account.
Otherwise, could you provide the relevant error message or screenshot when Authenticator won't work? Here are some possible solutions when logging in to Teams with the Authenticator that you can try:
- Make sure your device’s date and time are correct firstly, which can cause the authentication token to expire.
- Restart the computer to supply a new modern authentication token and try to sign in again. Sign out, and then sign in again using the old (or incorrect) credentials. After it fails, enter in your correct credentials.
- Delete all accounts from the Authenticator app and log in to your account again using the Device Registration option in the app settings.
Hope the above information is helpful for you!
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