Users located on our organizations 2010 Exchange server are receiving bounce backs when sending mail to users on our organization's 2003 SBS Exchange server.
Both servers are at different physical locations and do not share the same network or Forrest.
The only thing common on both servers is that they share the same primary email address.
The SBS 2003 Exchange server has an email address space of domain.ca, however, due to domain transfer issues, our organization does not have full control over our .ca domain and as a result were forced to create a .net domain for the new 2010 Exchange server.
In order for users on the new Exchange 2010 server to receive emails at their .ca address, we have setup individual forwarding for mailboxes so that mails first come to the 2003 server and is then forwarded to the 2010 server.
To quickly migrate some users from the old 2003 server to the new 2010 sever, we used ExMerge to convert user mailboxes to .pst files and then imported the .pst files to the newly created corresponding mailbox in the 2010 server.
The contacts were moved as well, and so what I believe is happening is that when users send emails to users who's mailboxes are located on the 2003 server, the 2010 server attempts to do this locally and throws back a "#550 5.1.1 RESOLVER.ADR.ExRecipNotFound; not found ##" error.
Below is the bounce-back report:
Generating server: SERVER.corp.domain.net
#550 5.1.1 RESOLVER.ADR.ExRecipNotFound; not found ##
I am really not an Exchange person, but have been thrust into this issue and am tasked with solving it.
Any help would be appreciated,