We have on premises mailboxes using Exchange 2003 and are looking to start a staged migration.
As a test I've migrated my own mailbox successfully, and mail routes to the cloud mbx fine. However I am unable to send to other internal users with on-premises mailboxes (all of them!). I can send to the internet fine.
Having followed the instructions for a staged migration, I did not see any reference to outbound connectors. How do I set exchange online to always send to the mx record (this dns record still points to our on-premises location)
Autoresolve works fine, there was never an on-premises record for this.
Regards
Andy