<header>SMTP server response on fqdn violation</header>

<center><tt>non_fqdn_reject_code</tt></center>
<hr>

This parameter specifies the SMTP server response code when a mail violates the
<tt>reject_non_fqdn_hostname</tt> or <tt>reject_non_fqdn_sender</tt>
or <tt>reject_non_fqdn_recipient</tt> rule that are:<br>
<i>Access denied: Invalid domain for client HELO hostname, sender or recipient email address (not FQDN)</i><br>
<br>
Note that the postfix default value used for <tt>non_fqdn_reject_code</tt> is
code 504, and this code in 'standard RFC 822' should means
'Command parameter not implemented'.
So with Postfix, a <tt>non_fqdn_reject_code</tt> rule violation does not reflect exactly
the RFC822 explanation of reported code.<br>
<p>
To avoid confusion, you can change this to 578 for example, otherwise, do not change
this unless you have a complete understanding of RFC 822.
</p>


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