Hi,
I have installed Exchange 2010 in mixed mode environment with 1 Exchange 2003 and 1 Exchange 2007 server. When moving some test mailboxes from 2003-2010 there is about a 20 minute delay in this moved mailbox from getting any mail. Afterwards incoming mail is normal. I was able to track this down to being that the messages were looping between Exchange 2003-2007, but without user intervention mail started flowing normally into the moved mailbox. This has happened every time mailboxes have been moved from 2003-2010. When moving from 2007-2010 there are no mail delay issues.
Setup:
Routing Group Connector (Cost 1) between Exchange 2003<->Exchange 2007 (this is original RGC).
Routing Group Connector (Cost 1) between Exchange 2003<->Exchange 2010 (mail headers indicate this connector is NOT being used for anything, 2003-2007 RGC used for everything)
Is this normal behavior?
Thanks.