Rule to force BCC with a Distribution List

Brass Contributor


I'm trying to build a rule to reject a message with explanation when a given Distribution List is used in fields "To" or "CC". The goal is to force users to use "BCC" with this DL.


So far I found the header "X-MS-Exchange-Organization-BCC" could eventually help but I'm not sure how to use it.

Help appreciated :)

1 Reply

Hi @Djavan ROA,


try to use a transport rule with condition


"When the recipient is a member of 'yourgroup'"


and  exception


"The To or CC box contains a member of 'yourgroup'"