Your Firewall and ListManager

If you have a firewall, you'll need to configure it properly so that ListManager can send and receive mail.

Living with a Firewall gives detailed instructions as to how to configure your firewall. Ports ListManager Needs Open is a handy reference of ports ListManager requires.

If you need internal mail to be routed in a particular fashion, see Utilities: Administration: Server: Server Settings: DNS Bypass.