Sending internal email from Exchange 2010 mailbox to Exchange 2003 fails with #< #5.2.1> #SMTP#
Posted on 2010-09-13
I've been looking at threads on EE all day and cannot really find why this is happening as my setup looks good. It has to be something I'm missing.
I have a newly installed 2010 Exchange Server installed in my domain that coexists with my Exchange 2003 server. All outbound/Inbound mail is being routed through Exchange 2010. I moved my account to exchange 2010 database via the 2010 EMC.
1. Outbound to External Sources (both 2003/2010)
2. From Ex2003 to 2010 Internal Mail
3. Inbound from External Sources (both 2003/2010)
What doesn't work?
1. Exchange 2010 sending mail to Exchange 2003.
Maybe someone to spot check me on a few things? I'm getting close to the end of my rope on this. Many thanks in advance!