Replace "https://" in that dialog with the mail server's name address, e.g imap.myserver.com and smtp.myserver.com then hit the get certificate button to fetch the certificate. If memory serves me right, you could also use the ip address and port combination, e.g 172.16.0.6:993

Sorry - should have been more clear. I was indeed removing the "https://" that is in the field to start with, and entering the name of my mail server with the appropriate ports per the various sites that directed me to that area of the settings. I tried "my.server.com:25" and "my.server.com:143" (which should work for SMTP and IMAP respectively using STARTTLS) and "my.server.com:993" and "my.server.com:587" (which should work for SSL). I did also try using the server's IP address. In every case it said "Unable to obtain identification status for this site" which is what made me think it was expecting a website.

Really, when setting up the account it should just say up front that it's a self-signed certificate and give the option to accept it. Even the old way (version 68 and earlier) of having to enter the details manually then try the connection to get it to ask to confirm the exception was a long-winded way to do it.

Try using the Authorities tab to import the CA cert.

Really, when setting up the account it should just say up front that it's a self-signed certificate and give the option to accept it. Even the old way (version 68 and earlier) of having to enter the details manually then try the connection to get it to ask to confirm the exception was a long-winded way to do it.

How would it know upfront that the account you're adding, is a self-hosted mail server using a self-signed certificate, and which automatic settings to use? Automatic fetching of settings happens for domains that Thunderbird knows about (in its database of known providers) or can "guess" from known domains.

I'll try importing the certificate, but it'll be tomorrow.

How would it know upfront that the account you're adding, is a self-hosted mail server using a self-signed certificate, and which automatic settings to use? Automatic fetching of settings happens for domains that Thunderbird knows about (in its database of known providers) or can "guess" from known domains.

Changing my dummy domain a bit... My email address is me@mydomain.com, and my mail server (both IMAP and SMTP) is mail.mydomain.com. The autoconfiguration correctly guesses the server, even detects that it can use STARTTLS, but then fails saying the credentials don't work. The only problem with the autoconfigured setup is that it hasn't accepted the certificate - if it just asked that one question, it would work perfectly.

I'll try importing the certificate, but it will be tomorrow.

How would it know upfront that the account you're adding, is a self-hosted mail server using a self-signed certificate, and which automatic settings to use? Automatic fetching of settings happens for domains that Thunderbird knows about (in its database of known providers) or can "guess" from known domains.

(I'll change my dummy server name to make this clearer.)

My email address is me@mydomain.com and my server (both IMAP and SMTP) is mail.mydomain.com. The autoconfiguration correctly guesses the server name from my email address, and even knows that STARTTLS will work. However, it says that it fails (I'm not sure of the exact message because I'm not at the machine with v78 on at the moment). Everything has been configured correctly by the autoconfiguration wizard, the only problem is the self-signed certificate. If it just asked that one question, it would work perfectly.