By Weldon Whipple <firstname.lastname@example.org>
SMTP (Simple Mail Transfer Protocol) Authentication lets you send e-mail from your e-mail client through a remote mail server to other e-mail addresses on the Internet.
If your ISP's e-mail server supports SMTP authentication (SMTP AUTH), here is how to configure the Mozilla e-mail client to send your user name and password to the mail server.
Note: Port 587 is the "submission" port for sending mail from clients to mail servers. If port 587 doesn't work for you, try port 25 (the SMTP port).
The above configuration should allow you to relay e-mail through mail servers that are configured for SMTP Authentication--assuming that you have a user name and password on the mail server.