Dmitry Streblechenko wrote:
As I mentioned bore, the header is only present on the incoming messages, it
will nto be present on the mesages in your Sent Items folder.

Thanks for the update. My concept of using headers and linking 2
messages together is removed. I guess the best method is then to put
some sort of key in the body and/or subject and hope the responder
doesn't wipe it out.