Originally posted this in the wrong forum. I think this may be an ISPConfig 18.104.22.168 bug but wanted to make sure, or see if there's a simple way to resolve this. Running Postfix/courier Linux 2.6.32-042stab055.16 #1 SMP Fri Jun 8 19:22:28 MSD CentOS release 6.3 (Final) Added an entry in Advanced Mail Routing for the domain to googles SMTP ip address. When I try to send an email using PHP's mail() function to any other email address, it works fine. When sending to an email address of a site on the local server, it tries to route it to localhost, where it doesn't find any email account because the mail account is on google apps remote mx: Mar 28 15:01:31 vds1 postfix/smtpd: NOQUEUE: reject: RCPT from localhost[127.0.0.1]: 550 5.1.1 <[email protected]>: Recipient address rejected: User unknown in relay recipient table; from=<[email protected]> to=<[email protected]> proto=ESMTP helo=<xxxxxxxxxxx.com> Mar 28 15:01:31 vds1 sendmail: r2SC1UVX000652: [email protected], [email protected] (48/48), delay=00:00:01, xdelay=00:00:00, mailer=relay, pri=30079, relay=[127.0.0.1] [127.0.0.1], dsn=5.1.1, stat=User unknown The domain xxxxxxxxxxx.com is added as a site, but not a mail domain. Do I have this configured wrong, or is something else wrong? This is causing a form to not properly deliver emails. Thanks!