Identify sender for a BCC-ed message from non-primary mailbox
I need to programatically identify the sender for those BCC-ed messages from
a non-primary (shared) mailbox.
The user has personal exchange mailbox and non-primary exchange mailboxs in
teh same profile. The message sent from those non-primary mailboxs is marked
as sent from the non-primary mailbox. The same message is always BCC (black
copy) to a third mailbox, against which an application tries to identify who
sends it. Does a property exist for it?