1. Open Mozilla Thunderbird.
2. On main screen click the "Email" icon under the "Create a new account":.
3. Select "Skip this and use my existing email" .
4. Type in your Full name, your email address and password, make sure "Remember Password" is checked, and click "Continue".
5. Next window will come up, click "Manual Configure" button right away.
6. Select "POP or IMAP" as server type for the Incoming section. Enter the incoming mail server, select the port (IMAP: 143 POP: 110). SSL, select what your provider supports, most . Under "Authentication" select "Normal Password" unless directed otherwise by your host.
7. Outgoing SMTP Settings: Type in your outgoing mail server, select your Port (most use 587 these days). SSL, select what your providers supports, most just say "none", and for "Authentication" select "Normal Password"
8. Under the Username section for both Incoming & Outgoing, type in your full email address. Then click the "Done" button. NOTE: There is a known bug with Thunderbird's "Re-test" button, so DON'T use it.
9. Thunderbird may warn you if you don't have a secure connection for your email, just check the button that you agree and complete the process.