An existing exchange 2003 sp2 with an internet mail connector is unable to send mail to the new exchange 2007 (sp1) server on windows2008. I can send mail from the 2007 server to the 2003 server and also out to the internet via the 2003 server but mail to a user whose mailbox i moved from 2003 to 2007 ends up in the "olserver-newserver (Routing Group Connector)"The additional queue information reads "The connection was dropped by the remote host"exchange 2k7 has hub transport, client access and mailbox roles.I've turned up logging on the exchange 2003 server but this does't show me anything useful.I can telnet to the exchange 2007 on port 25 but it drops after I do the mail from command as I didn't authenticate myself.

Fixed this one thanks to a post on petri at http://tinyurl.com/6y2a8c - post 2 has the answer - namely remove the smarthost setting in the virtual server on the exchange2003 server. Then mail will use the routing groups and everything is ticketyboo.Many thanks to the other Andy for the answer on this one.