Try this: incoming server: imap.aol.com, port 993, SSL/TLS, normal password outgoing server: smtp.aol.com, port 587, STARTTTL, normal password

AOL are using 'OAuth2' authentication instead of 'normal password'. This goes for both, the incoming, and outgoing server.

Also, for the outgoing server, this should be STARTTLS, not STARTTTL.

Thanks, Christ1. It's puzzling, as my account works with normal password. Yes, that was my typo; it should have stated STARTTLS. :)

AOL allows 'normal password' authentication on apps that don't support OAuth2, like the gmail Android app or W11 Outlook, but the password must be an 'app password'. TB, of course, supports OAuth2 for AOL, the preferred method.