|Remember 'server settings' and 'outgoing sever' are in different places and you need to get both right.|
Are you absolutely sure that you are using the same letters, numbers, symbols, and capitalizations? Have you thought of trying a different password that might translate on different devices easier?
Check your mail supplier to see if they have updated, newer, or optional settings or ports that might work better.
If all else fails, back up your contacts, uninstall, and reinstall Thunderbird.
Another thought, if you had made any changes or updates around the same time as you changed passwords, you might try a system restore to before that, confirm that the email works, and try the change, install, or update again.
You have to be a little bit crazy to keep you from going insane.