Hi, On Wed, Jun 17, 2009 at 19:48, nate<centos at linuxpowered.net> wrote: > header_checks = regexp:/etc/postfix/regexp_table > > and in /etc/postfix/regexp_table something like: > /^Subject: This is the subject I want to reject REJECT 554 Custom rejection message You missed a "/" to close the regexp... If you want to discard the message you can use DISCARD instead of REJECT. See the ACTIONS section of "man header_checks" or the manpage here: http://www.postfix.org/header_checks.5.html It should be something like: /^Subject: Rejected posting to / DISCARD Delete returns from listserv The "Delete returns from listserv" message will appear on your logs, so it will be easier to see which (or how many!) messages are being discarded. HTH, Filipe