I'm strugling to configure the Global Mailbox option to deliver emails BCC'd to the intended recipients mailbox within Exchange2003.

The BCC email gets delivered to the address entered in the Failsafe field. Is not the purpose of BCC to deliver a 'blind copy' to the intended recipient in confidence?

I'm sure I have messed up somewhere and would appreciate some help.

Unfortunately due to the way BCC works, it is impossible for POP Collector to deliver these emails correctly. They will only be delivered to recipients in the To: or the CC: fields - or if these are blank, to the failsafe.

The reason for this is that when an SMTP server sends a message to a BCC recipient, there is no record of it placed in the message headers (unlike To: and CC:). This is why it is blank. When the message reaches it's final destination, the BCC (which is held in the SMTP envelope) is discarded. The final destination of the message is the end of the SMTP journey - so when it is in the POP mailbox for POP Collector to retrieve it, any BCC information has already been removed.

Hope this makes sense.

...However, there are lines in the header that the software could parse, like "Delivered-To: " or similar. Many mailing lists (that are the common sources of bcc mail) use that, and it would be nice to recognize these, and/or have an administrative option to set rules based on custom header lines.