Hi,

We are migrating to Exchange 2013 from 2010 and all is setup with the best practice in mind. The problem is that we are changing namespaces at the same time, going from one of the subdomains (x.org.com) to the forest level (org.com). The 2010 virtual directories is set to the new namespace (org.com) and provider is also set to the new namespace. Outlook client is behaving as expected when moving mailboxes to 2013 but Activesync clients just stops working. After manually changing the server address on the mobiles its all working again, but I don't like the sound of the manual labor.

Testing with Connectivity Analyzer shows that the old server does not give me an 451 return with the new address but just a 403 failure with Access denied when I test with an non-administrative account that has mailbox already moved to 2013. If the mailbox is still on the 2010 the ExRA returns success and likewise if I test with the moved mailbox and the 2013-server. 

So is there any suggestions how I can generate the 451-return to the mobiles so the namespace change can be done without manual interventions on the Activesync devices?

Regards,
Stefan

Hi 

" The problem is that we are changing namespaces at the same time, going from one of the subdomains (x.org.com) to the forest level (org.com). The 2010 virtual directories is set to the new namespace (org.com) and provider is also set to the new namespace."

Have you acquired a  new domain x.org.com to your forest org.com

The 2010 virtual directories is set to the new namespace (org.com) and provider is also set to the new namespace - This part of the question is confusing.

Can you explain little bit more so people can help you out here 

Sorry if my explanation is more confusing than clarifying :).

The subdomain x.org.com is an old one, having an single exchange 2010 server named exchange.x.org.com and autodiscover.x.org.com.  Now we want to move mailboxes to new exchange 2013-servers at the organization top level domain named exchange.org.com and autodiscover.org.com. DNS records exists and I use the same certificate for all servers.

With the provider I mean the EXPR setting in Outlookprovider on the 2010 server - we want the clients to use the 2013 (exchange.org.com) as proxy for the 2010 mailboxes.

Or am I doing this totally wrong when migrating to another namespace (even though migrating from a subdomain to a top level domain) and at the same time migrate from 2010 to 2013?