I've never come across this before, but I've never run Outlook 2010 with Exchange 2010 before either. I have a login that is an Exchange Organization Administrator and I'm logging on to a 64-bit Windows 7 PC running Office 64-bit as well. In order to run mailbox imports, I gave this login Full Access permissions to all of the user mailboxes on the Exchange 2010 server. I also have the Exchange 2010 management tools installed. What is happening is that when I open Outlook it is opening all of the mailboxes to which I have full access permissions. I can edit the Account Settings while Outlook is open and remove those mailboxes, and then they close, except for one particular mailbox for some reason. But the next time I open Outlook, it re-adds all of those mailboxes to my account settings.
Has anyone ever experienced this? Is this by design or is there some way to prevent it? I really don't want to have all those mailboxes opening all the time. I only need the Full Access permissions for occasional issues that I may need to troubleshoot.