Amavisd-new provides Policy Banks that allow you to manage messages based on the client or sender.  For example if you wanted senders to be able to send to email lists without using the server resources for scanning with Spamassassin and ClamAv for these outgoing messages you could create a Policy Bank Solution: Specify Clients Who Can Bypass Scanning This solution will allow the mail server to avoid the scanning process to save on system resources, ...

The vacation program is not built specifically for Postfix.  So you will need to set it up separately from Postfix and then integrate it. The vacation feature allows you to configure a message that will be returned to the sender when you are out of the office.  If you are using a CentOS version you will not find vacation in any ...

Listed here are a number of header checks that do work but they are ineffective for the most part.  Here is the problem.  When you look at these examples they have a Subject that you are searching for.  As a result you will be writing header checks until the day you die, not good.    My thinking is that you will want to discard ...

Header checks with Postfix can be used to deal with unwanted mail before your server wastes time with it.  Created the file /etc/postfix/header_checks and then add this line in your main.cf. header_checks = pcre:/etc/postfix/header_checks The format line for each header check follows this ...

One way to implement content filtering is to use regular expressions in your header, mime_header, nested_header and  body checks.  This should be simple matches to regular expressions.  The goal with this example is to eliminate non-English characters, since we cannot read them anyway.  This will drop all non-English ...