So I am trying to add my company email to Thunderbird and am still currently getting the error message "Thunderbird failed to find the settings for your email account.". I have confirmed that all of the input information is correct as I am able to add the same account in Outlook. For incoming I am using IMAP at mail.*company*.com on port 993 with SSL/TLS and normal password authentication For outgoing I am using smtp at smtp.*company*.com on port 465 with SSL/TLS and no authentication. I have reset my email password to make sure I am using the most current one and I have even temporarily disabled my local firewall/antivirus to make sure that wasn't the issue, and I have done a fresh installation of Thunderbird with to change. These exact settings work perfectly in Outlook and on multiple other user's machines, and I have quadruple checked that the settings are correct. I also can't click on "Advanced config" while the error message is there. I don't really know what else to do here but abandon using Thunderbird. EDIT: I will also add that Thunderbird worked perfectly fine until last week when we switched over from port 143 to 993 (this is just an internal company email) and that is when the problem started however it is with the same updated settings that everything is working on other machines. So I know Thunderbird has been able to work before on this machine.