I have 5 sites in my org all having local Exchange 2003 servers. All mail comes into the org thru a 3rd party mail gateway (Tumbleweed EMF) and then is forwarded to our corporate headquarter exchange server and then mail is routed from there. All exchange servers relay outbound mail directly to the internet. I would like to route mail from our corporate headquarters to our mail gateway.
I tried using the smart host feature under the SMTP Virtual server, but caused a routing loop with internal mail between exchange servers. Outbound mail worked, but we need both.
How to I setup exchange to route only outbound mail thru the mail gateway.