To add an email account in Thunderbird:
Open Tools » Account Settings » Account Actions » Add Mail Account
Fill in the name, full email address (firstname.lastname@example.org) and password), click Continue.
Thunderbird will try and figure it out, but manual settings are usually needed. Click Manual config
|Outgoing:||SMTP||Port:||587 / 465||SSL:||STARTTLS||Auth:||Normal password|
Incoming and Outgoing server: mail.yourdomain.com
For the imap/smtp server, use the value your host gives you. It might be mail.domain.com, but could also be the server.hostname.com, depending on how they've setup their SSL certificates. If you do get ssl certificate warnings, just accept them. The connection is likely still secure, as the value in the certificate might not match the server setting used (not a major issue).
- Click Done as re-test does not work for this case.