Hello,
I am currently migrating from Exchange 2010 to Exchange 2013 (CU5) and am encountering problems with the proxying of ActiveSync from 2013 to 2010.
Users who still have a mailbox on Exchange 2010 will receive an error that the server cannot be reached on their iPhones. We are using Client Certificate-based Authentication, which is working fine for users that have a mailbox on Exchange 2013.
We are using self-signed certificates and have made sure the root cert and client cert are on the phones with the iPhone Configuration Utility.
The iPhones are connecting to the Exchange 2013 CAS Servers from the Internet via a NAT rule on the firewall, which was used for the 2010 CAS servers before. We only changed the destination IP. It is not working on the LAN either.
All other Exchange services work fine. OWA via Exchange 2013 is running smoothly for users who are still on Exchange 2010.
I hope anyone can shed some light on this issue for me. I will gladly supply any further information needed.
Regards,
Arjan.