We have Outlook 2007 and 2010 clients to a Exchange 2007 mail server. When Outlook is started, it can take 60 seconds or more to display items in the Inbox. Then it functions normally. The folders in the left-hand panel are immediately there with new mail counts.
The only change I can think of is that we implemented a new Windows Server 2012 domain controller about the same time. The old DC got a new IP address, and the new DC got the old IP address as this is our main DNS and DHCP server as well - needed to keep the IP address. (The old DC will be retired shortly.)
Could the new 2012 DC be causing this problem somehow? Or something else?
Thanks for any assistance.