When I connect a new client to my Exchange 2010 server, I get the message "Unable to open you default e-mail folders. The Microsoft Exchange Server computer is not available. Either there are network problems or the Microsoft Exchange server computer is down for maintenance."
All other clients that were existing in the past can connect without an issue, but no new clients can connect. It doesn't matter what version of Outlook. BUT - I can connect using the OWA client to that user without any problem. Even if any firewall is turned off, still no connection can be made.
There are no errors in the Windows event log, Exchange event log, or the local workstation that tries to make a connection. All workstations are on the same subnet and connected directly via 1GB switch joined to the same domain.
Running Exchange 2010SP1 on Server 2008SP1.