I am using Pair.com
They gave me this info:
Outgoing Server: vqs663.pair.com
Outgoing Port: 465 with SSL on
Outgoing Authentication: On
Username: USER@DOMAIN.COM (where USER is the mailbox username, and "@DOMAIN.COM" is your domain. Remember to include the "@DOMAIN.COM" part of the username)
Password: [your password]
I have been able to setup Outlook to use the mail account, but not the webpage.