Under Channels > Email > Other I've enabled Create tickets on behalf...

I forwarded an email sent directly to myemail@mydomain.com to the support address after adding a single line to the top of the body "#original_sender { requestersemail@theirdomain.com} and the email never showed up in desk (not as a ticket for the requester or from me).

I also just tried sending a test ticket in from myemail@mydomain.com to the support address and there is no ticket created.

Any help would be appreciated.