- You deploy Microsoft Exchange Server 2013 and Microsoft Exchange Server 2007 in a co-existence environment.
- Either of the following conditions are true:
- You don't configure a legacy namespace for Exchange Server 2007 EWS traffic.
- You configure a legacy namespace, but you don't configure your EWS application to utilize Autodiscover.
OWA uses silent redirection to the legacy namespace. However, EWS does not support silent redirection. Therefore, the default behavior for Exchange Server 2013 is to proxy the traffic that is directed to legacy servers. While this works as expected for Exchange Server 2010 EWS traffic, it is not reliable in Exchange Server 2007. Instead, you should manually redirect the EWS client traffic to the legacy namespace.
For more information about namespace planning in Exchange Server 2013, see the following Exchange Team Blog article:
For more information about Legacy namespaces in Exchange 2013, see the following TechNet topic:
Article ID: 3152392 - Last Review: Apr 6, 2016 - Revision: 1