I keep getting this, i know how i screwed up but i dont know how to fix it. When i followed the ispconfig guide i forgot to run and edit /etc/hosts echo server1.example.com > /etc/hostname /etc/init.d/hostname restart I did it now but it still doesnt work Code: Mail Delivery System <[email protected]> 2:37 PM (32 minutes ago) to me This is the mail system at host techreanimate.com. I'm sorry to have to inform you that your message could not be delivered to one or more recipients. It's attached below. For further assistance, please send mail to <postmaster> If you do so, please include this problem report. You can delete your own text from the attached returned message. The mail system <[email protected]>: unknown user: "luis" Final-Recipient: rfc822; [email protected] Original-Recipient: rfc822;[email protected] Action: failed Status: 5.1.1 Diagnostic-Code: X-Postfix; unknown user: "luis" ---------- Forwarded message ---------- From: Luis Rodriguez <[email protected]> To: Luis Rodriguez <[email protected]> Cc: Date: Sat, 22 Jun 2013 14:37:20 -0400 Subject: sdfgsdfg dfsgdfg