I have been having some problems configuring the mail server (I use postfix) on my VPS. I have set it up along with Virtualmin and Webmin and it can receive mail fine, however the problem it has it that it cannot send the mail to an external server. (It's fine to send it to another domain on my server). The error I get in my log is: (The email address I'm sending to is @btinternet.com) Code: Host or domain name not found. Name service error for name=btinternet.com type=MX: Host not found, try again I have been experimenting and I realised I cannot ping the hostname of any site (although, I can dig it), however I can ping the IP of any server. I'm guessing that my problem is probably due to this, however my experience with Linux is letting me down and I have been struggling to fix it. Operating System: CentOS 6.0 Main Domain: webemblem.com (DNS should be set up properly) Anyone have any ideas? EDIT: I have now fixed this problem after hours of searching and testing and stressing. Basically, when I installed Virtualmin (a domain management program) it incorrectly configured my /etc/resolve.conf, so I went and edited this to what it should be and this fixed all of my problems.