I used to use event sinks to create a catch all mailbox with 2000 and 2003. With 2007, I tried to use Transport Rules to forward a copy of mails from External Users to recipients who where NOT members of a dynamic distribution list containing all mailbox users. Thus a mail sent to wibble@domain.com should have been forwarded to the postmaster, but instead was just bounced back to the sender as undeliverable. Has anyone got any clues why my method doesn't work, and/or how I acheive a catch all mailbox using Exchange 2007? Thanks in advance.