If the window Welcome to Thunderbird opens when you start Thunderbird for the first time, then choose I think I'll configure my account later.

→ Click the Alt key on your keyboard to see the the menu row on top of the window.
→ Choose Tools and Account Settings. → Click Account Actions and choose Add Mail Account.
→ Your name: Is the name you want the receiver to see as sender.
→ Email address: Your email address.
→ Password: Your email address password.
→ Remember password You probably want Thunderbird to remember the password.
→ Click Continue and choose Manual config.

→ Incoming: should be IMAP.
→ Server hostname is mail.1984.is
→ Port 993 SSL/TLS
→ Authentication Normal password.

→ Outgoing: SMTP
→ Server hostname is mail.1984.is
→ Port 587 STARTTLS
→ Authentication Normal password.
→ Username: Incoming: Your email address, Outgoing: Your email address.
→ Click Done (or Re-test).

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