I have a (possibly reoccurring) problem with our Exchange 2010 SP1 box. The server hosts all roles (hub transport). The problem started last week where after I restarted the server for maintenance, random Outlook clients could not connect. When trying to setup a new Outlook account (even deleting all old profiles) the username could not be verified with the exchange server. We have RPC encryption turned on via group policy for the legacy 2003 clients, and even some of the 2007 and 2010 users have problems. But only certain people are affected by this - while others continue to connect and work without problems. Some are marked as offline, and have no way of changing it to "online" as there normally is.
I've narrowed it down to it being an RPC error due to running portqry and finding no connection to the UUID: f5cc5a18-4264-101a-8c59-08002b2f8426 MS Exchange Directory NSPI Proxy ncacn_ip_tcp:srvr005
The command I ran was "portqry -n (exchange server) -e 135"
I say this is a reoccurring problem because it happened one other time, last week. The last time this happened, the problem resolved itself after about 8 hours. Today, we are still having the problems this time well after 8 hours. I'm losing faith that it will resolve itself this time.
Strange thing is - we can setup an Outlook client successfully if we put the global catalog server in as the exchange server in a new outlook profile and then the username resolves and the correct exchange server name maps properly. Email works happily after this is done.
Can anyone provide any insight as to why this is happening and how to resolve the problem correctly? I've already gone through a MS article which describes registry entries and proper DLLs in place. Since this resolved itself last time - I still feel as though it may resolve itself this time, but want to be able to restart my exchange server without this problem (and on the off-chance it doesn't start working, to help fix it)
Thanks in advance,