Comment:
Update to incoming server settings. Previously STARTTLS/143, now SSL/TLS/993
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In the Home or Inbox tab of Thunderbird, click the Thunderbird Menu to the right of the Search bar then click Account Settings.
OR, go to Tools then Account Settings.
Click Account Actions, then Add Mail Account.
Enter your name and email address but do not enter your password. Click Continue.
NOTE: if adding a Resource Account or Shared Email, enter the Display Name and Email Address of the Resource Account.
Thunderbird will attempt to discover the server configuration. If it fails to find the server configuration, enter them as follows then click Done:
NOTE: If you're adding a Resource Account or Shared Email, enter the Username as follows for the Incoming and Outgoing Server: Your-Email@austin.utexas.edu\Resource-Account@austin.utexas.edu
INCOMING SERVER
Protocol: IMAP
Hostname:outlook.office365.com
Port: 143993
SSL (Connection security): STARTTLSSSL/TLS
Authentication: OAuth2
Username: Your UT email
OUTGOING SERVER
Hostname: outlook.office365.com
Port: 587
SSL (Connection security): STARTTLS
Authentication: OAuth2
Username: Your UT email
A window with a UT Login will appear. Login using your EID credentials then authenticate with Duo.
You may be returned to the account configuration screen and see a message saying "Unable to log in at server". If so, click Done.
Then on the Account successfully created screen click, Finish.