Environment - 1 Exchange 2003, 2 Exchange 2007 ( 1CAS, 1mailbox, hub transport).We have internal app servers that need to relay off the hub transport server. I have read this article http://msexchangeteam.com/archive/2006/12/28/432013.aspx.Currently, the app servers use their local smtp service and use our Exchange 2003 server as a smart host. Relaying on the Exchange 2003 server is restricted by IP.In reading the article above it states thatallowing relayingis simple because by default authenticated servers are allowed to relay. I guess I'm not quite sure how to set up our app servers to authenticate. Thanks

Youmay want to go back and re-read that article a little closer. You should find the section that starts as follows:------------Begin Quote--------------- Only the list below (specify IP address) This option is for those who cannot authenticate with Exchange. The most common example of this is an application server that needs to be able to relay messages through Exchange.------------End Quote----------------This seems to fit your scenario. You will need to create a new Send Connector using the directions in the article. Then you will need to follow either Option 1 or Option 2 to apply the necessary permissions to that Send Connector to allow your app servers to relay.Hope this helps.LeeLee Owens

Yes. I read that. I guess my next question would be, what servers can authenticate through Exchange. These app servers are running IIS with SMTP installed. Can they not authenticate somehow?