Looking for knowledge on the co-existence between Exchange 2010 and 2003. We have successfully setup and configured 4 Exchange 2010 servers (1 Hub/Mailbox, 1 Mailbox, 1 CAS, 1 ETS) We have been able to create and migrate a mailbox from 2003 to 2010, however communications between the migrated mailbox and the previous 2003 exchange system does NOT work. The mailbox on the 2010 server is able to be accessed from the CAS owa and we're able to generate traffic from the ETS (Edge Transport) to the 2010 mailbox.
There are two exchange 2003 servers that the new 2010 infrastructure will have to co-exist with for a period of time. One 2003 server is local and part of the same domain as the 2010 servers, the other is a member of another domain, all part of the same forest. All the Active Directory requirements have been meet for the implementation of 2010, the DAG has been setup and configured and all is operational.
We think the issue lies within the intra or site connections and how 2003 has to be configured to talk with the 2010 organization. The 2003 organization has the original two routing groups with connectors. From the 2003 System Manager, the 2010 Admin Group has the EdgeSync connectors and that is it. Do we need to setup new routing group connections on 2010 for the 2003 communications? If so what is the best way to create these connections and test after implementation?