Exchange 2010 - Exchnge 2003 Co-Existence

[mobiledynamics]

Migration from 2003 to 2010.

I can send and receive within 2003 to internal/external.
From external address, I can send to a user that is migrated to 2010 (with MX still pointing to 2003 box) and mail arrives into user that is in the 2010 box.

On the test ~moved~ 2010 user, mail is received fine from external and internal users.
HOWEVER, I cannot sent to ANY user that is internal on the E2K3 box.

I get a #550 5.1.1 .
Can anyone please advise.

 

[58sniper]

Look at your routing group connectors and verify that the correct source and target servers are listed.

Pat Richard MVP
Plan for performance, and capacity takes care of itself. Plan for capacity, and suffer poor performance.

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