If your email address ends in @meganet.net, @naisp.net, @xpres.net: 

Standard:

Incoming mail server: mail.meganet.net
Incoming mail server port: 110 for POP3 or 143 for IMAP (What's the difference?)
Username: youraddress@meganet.net (you MUST use @meganet.net, even if you have @naisp.net or @xpres.net as your email).

Outgoing mail server: mail.meganet.net
Outgoing mail server port: 587 for SMTP
Username: youraddress@meganet.net* (you MUST use @meganet.net, even if you have @naisp.net or @xpres.net as your email).

*Your username and password is required for the outgoing SMTP server (some programs will say it is optional).

Secure (SSL/TLS):

Incoming mail server: mail.meganet.net
Incoming mail server port: 995 for POP3 or 993 for IMAP (What's the difference?)
Username: youraddress@meganet.net (you MUST use @meganet.net, even if you have @naisp.net or @xpres.net as your email).

Outgoing mail server: mail.meganet.net
Outgoing mail server port: 465 for SMTP
Username: youraddress@meganet.net* (you MUST use @meganet.net, even if you have @naisp.net or @xpres.net as your email).

*Your username and password is required for the outgoing SMTP server (some programs will say it is optional).