Hi, I have this problem my email server's DNS name is ns1.mydomain.com, and it is registered in the reverse DNS also with that name, when i installed my server at the hostname i entered centos-server.mydomain.com when i tried to send an email from the root console with # mail root the email is returned saying that root at centos-server.mydomain.com, could not be verified i used the command # hostname ns1.mydomain.com and also edited the file. /etc/hosts, but i have the same result, the hostname did not change, i even restart my server with no luck. what am I missing? regards, Guillermo. PS my server is a CentOS 4.4, with postfix -- Guillermo Garron "Linux IS user friendly... It's just selective about who its friends are." (Using FC5, CentOS4.4 and Ubuntu 6.06)