Thunderbird login passwords are not working

- What version of Thunderbird? - What is your operating system? - Who is your email provider? - Is this an IMAP account or POP3? - What error messages do you see? Please quote them precisely and in full. Screen shots would suffice. - Have you confirmed that the password that Thunderbird has stored is, indeed, your correct current password for your email provider? Passwords are stored at <Settings | Privacy & Security | Passwords | Saved Passwords>. Keep in mind that if your account uses OAuth2 as the authentication method, your actual password won't be found there, but instead you will see what's known as a "token", which is a long string of arbitrary characters. If this is the case, report back here and we'll advise you what to do next.