One of these actions is take when the message matches one of
the content filtering rules, meaning, the top-level
content type matches one of the <a
href="?VARHELP=contentfilter/filter_mime_types"
>filter_mime_types</a>, or the top-level content type does
<strong>not</strong> match one of the
<a href="?VARHELP=contentfilter/pass_mime_types"
>pass_mime_types</a>, or if after filtering the subparts of the
message, the message ends up empty.
<p>Note this action is not taken if after filtering the message
still contains content. In that case the message is always
forwarded on to the list membership.
<p>When messages are discarded, a log entry is written
containing the Message-ID of the discarded message. When
messages are rejected or forwarded to the list owner, a reason
for the rejection is included in the bounce message to the
original author. When messages are preserved, they are saved in
a special queue directory on disk for the site administrator to
view (and possibly rescue) but otherwise discarded. This last
option is only available if enabled by the site
administrator.
