Dear all, I followed "The Perfect Server - CentOS 5.3 x86_64" Everythings work perfect, except that I cant receive email from external. when trying to send email from Gmail to mydomain email, I got: The error that the other server returned was: 550 550 #5.1.0 Address rejected [email protected] As I disabled the firewall, ports shall not be blocked. Any hints or where to look for the error for email receiving. Thanks Levin