My mail system on Debian is down, whenever I send an email to someone, anyone, I get a the following report attached as a txt file: Reporting-MTA: dns; mail.*****.net X-Postfix-Queue-ID: B14725482B6 X-Postfix-Sender: rfc822; Arrival-Date: Mon, 2 Mar 2009 10:16:59 -0800 (PST) Final-Recipient: rfc822; l.**@raz.bgclamav Original-Recipient: rfc822;l.**@raz.bgclamav Action: failed Status: 5.4.4 Diagnostic-Code: X-Postfix; Host or domain name not found. Name service error for name=raz.bgclamav type=A: Host not found I searched Google for restarting the mail server but oddly enough I can't really find a solution, so at the end I simply tried 'restart mail server' which didn't work. I think this problem arised after I install Clamav (anti-virus especially for mail). When I noticed mails weren't sending out anymore I removed the app, but I still have problems. Can someone please tell me how I can fix this issue? Should I restart the mail service and if so how? Thanks a lot!