Hi @Ahra_G    That article you linked advocates using a none secured connection - which is bad.   The other comments made about changing the Thunderbird config are better than what TPG support has suggested.       ... View more

This is not a solution, but a very poor work around.   TPG support should not advocate using unsecured connections.  That is just sad.   Thunderbird has deprecated out of date connection protocols - which TPG still use.   The proper solution would be to have TPG update their mail server to support the latest protocols.   A less worse work around is to enable the use of outdated protocol connections (still bad) in ThunderBird so you can get TPG emails.     This is what has happened and how to change in ThunderBird config to get it to work with TPG https://support.mozilla.org/en-US/questions/1295861   This is where I found the information https://community.tpg.com.au/t5/Broadband-Internet/TPG-email-account-inaccessible-with-Thunderbird-78/m-p/74437           ... View more