So I changed from a single Exchange setup to a front end/back end setup using the existing server as a front end server and moved all of the mailboxes to a clustered back end Server. Everything is working(except iPhones), we even have blackberry Enterprise server with blackberry phones that are all working. Before the change iPhone 3G were working and using the OWA external DNS address using IMAP.
Every since I moved mine and everyone's mailboxes to the back end server, the iPhones will not update. I have added the IMAP Clustered service and is started following the microsoft white paper on how to setup the IMAP service on a clustered server. The front end Server IMAP configuration has remained the same. The service is up and running as I can telnet to the ports via 143 and 993 on both the front end and back end servers. What is different is telnet to the front end port 143 gives me "* Bye Connection refused". I assume that is because it is set to "require secure channel" in the IMAP properties under communication.
I assume that in the front end/back end configuration that the front end will get the IMAP request and send it on down to the back end server that has the mailboxes. I have not been able to find a true answer to this. Again this worked before when it was just a single exchange setup where everything was on the one server. What could be the problem here? Email, OWA is flowing just fine.
So with my iPhone it again has not been able to connect since the move to the back end exchange server. And to be even more specific it was not the change "checking the box making it a front end server and rebooting" that did it. I waited to move my mailboxes to the last one. As soon as I moved it to the back end server is when it stopped working. I have not tested this out yet but I am willing to bet that if I create a mailbox on the front end server it will work.
I even tried to take out the exchange account from the iPhone and add it back in. I know it is not a port issue with the phone trying to connect as I have VPN'd from the phone so it is on the inside of the network and it still cannot connect. It is stuck trying to add the account and will not do anything. Any suggestions? Sorry for the long post but I figure the more information the better.