Hi,
I'm trying to troubleshoot an Outlook connection issue in an environment where a CAS Array was introduced and assigned as the RpcClientAccessServer for one database, lets call it DB4.
Few things to note
1. RPC/HTTPS (Outlook Anywhere) is the only connection method allowed (internally and externally)
2. RPC is blocked on the firewall
3. Outlook Provider for EXPR and EXCH is set to ServerExclusiveConnect
4. The CAS Array object is not externally resolvable
5. Using split DNS where the webmail/autodiscover URL is internally and externally resolvable
6. The CAS servers are sitting behind a load balancer and only port 443 is allowed through
The problems becomes apparent when any mailbox is moved into DB4 and you try to set up a new Outlook profile. Autodiscover finds all the correct settings but when opening Outlook you get a 'work offline/retry' prompt, strangely enough when you click on 'retry'
the mailbox opens (this is the case every time).
It appears the initial Outlook connection attempt is using RPC, which times out and you get the retry prompt. On databases which aren't "using" the array the RPC attempt would also time out but then the connection is established with RPC/HTTPS
automatically.
I thought 'ServerExclusiveConnect' forces the connection via RPC/HTTP, so the client shouldn't attempt RPC?
I've gone through the two blogs below but might have missed something. If anyone has any ideas on what else could be causing this please let me know.
http://blogs.technet.com/b/exchange/archive/2013/05/23/ambiguous-urls-and-their-effect-on-exchange-2010-to-exchange-2013-migrations.aspx
http://blogs.technet.com/b/exchange/archive/2012/03/23/demystifying-the-cas-array-object-part-1.aspx