Block bcc mail on exchange 2010/2013


  • Hi all,

    I have been searching how can i block send bcc mail to inside/outside . I couldn't find a solution about this issue. I tried to create transport rule with message header and text pattern X-MS-Exchange-Organization-Recipient-P2-Type: Bcc . It  is still passing bcc mail inside and outside. Is there a way to block bcc mail when sending an email. Thanks in advance


    Wednesday, February 1, 2017 1:53 PM

All replies

  • I don't know of any way to do this natively in Exchange.  Do you understand what a BCC recipient is?  It's someone who's addressed in the envelope but not in the headers so that he gets a copy but his name doesn't show up in the copies delivered to others.  That's why you won't find anything in the headers that will tip you off.

    I suppose that if you had some kind of messaging hygiene service, it could check to see if the envelope recipient is not listed in the headers and then bounce the message, but I don't see how to accomplish that in a transport rule.

    It may be possible to block the display of the BCC box in Outlook through group policy.  The Outlook forum would be the place to ask about that.

    Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."
    Celebrating 20 years of providing Exchange peer support!

    Thursday, February 2, 2017 1:38 AM
  • Hi Ed,

    Thank you for your comment, Outlook client can access to bcc via using address book tab,even if you use group policy for gpo, Spam gateways of some added block bcc option but they removed that future than there was some confusion to block bcc. I guess there is now way to make it.

    Thursday, February 2, 2017 1:12 PM
  • Hi,

    Is this Exchange 2010 or 2013?

    If it's Exchange 2010 you can buy a ready made custom transport agent to remove BCC here.

    If it's Exchange 2013 you'll need to write you own one - read here.

    Have a great day,


    Oliver Moazzezi | Exchange MVP, MCSA:M, MCITP:Exchange 2010,Exchange 2013, BA (Hons) Anim | | |

    Thursday, February 2, 2017 2:51 PM
  • Aha - so there is, I missed that.

    Beats writing your own solution!

    Oliver Moazzezi | Exchange MVP, MCSA:M, MCITP:Exchange 2010,Exchange 2013, BA (Hons) Anim | | |

    Monday, February 6, 2017 10:14 AM