Ray wrote:
2) "smtpd_delay_reject = yes" is set, so try to figure out sending ip address and search for it in maillog.
Er, I meant the opposite. If smtpd_delay_reject=yes is set, then the mail logs should have recorded everything from the sender's domain to the intended recipient at some point. The premise is that Postfix will delay rejecting the message until it has logged some useful information.
So if that's set, you probably don't have to hit up the sender for his or her outgoing IP addresses--the domain would have appeared in the logs.
