Detecting the use of BCC from the content filter

This is a simple content filter rule that will help you in filtering messages where the current destination was BCC’d rather then being listed in the TO or CC field.

Note that this will trip on most mailing lists — This is correct behaviour, unless the mailing list fills in the recipient’s name in the TO field (and most do not), lists are essentially using BCC.

It only works reliably in the LocalQ, it won’t work in the RemoteQ unless you turn off smartspooling, and it only works for mail received via SMTP, not MultiPOP or DomainPOP.

[Rule001]
RuleName=Detect BCC’d messages
Enable=No
ThisRuleCondition=All
ProcessQueue=LOCAL
Condition01=TO|does not contain|AND|$HEADER:X-Rcpt-To$|
Condition02=CC|does not contain|AND|$HEADER:X-Rcpt-To$|
Action01=add header|”X-BCC”,”True”

To use this rule, copy the above text and paste it into the very top or very bottom of your MDaemonAppcfrules.dat file using Notepad, then open the content filter dialog in MDaemon and enable the rule.

No semaphore files needed, no need to restart MDaemon.