It turns out the actual bug is with Thunderbird. If you use your existing profile and change the IMAP software running on the same email server, then, even if you modify the Thunderbird accounts you were using to point to no server, and eliminate all visible config that might conflict, including saved password, then, you new accounts (but same username) to the same email server with different IMAP software (in my case switching from cyrus-imap to dovecot; I uncovered this by trying to switch back to cyrus-imap and having the same issues (the email server had to have been rebuilt due to hardware failure, and I had decided to switch IMAP software at the same time)).
It seems Thunderbird doesn't like it when you don't start with a fresh profile in this type of scenario. Regards, Daniel -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1420648 Title: Client certificate verfication fails To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/dovecot/+bug/1420648/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs