BCC property will internally scan headers and search
for 'BCC' header, and return its information to
you. Before it does that, it will decode the value if
UNICODE was used so that you get printable expression in
your applications. If there is more than one recipient, it
should be divided by comma character.
When you set this property, it will overwrite
'BCC' header.
Blind carbon copy recipients means that each recipients
only sees himself as the recipient of the message, and does
not know the other recipients (as when CC field is used).