Notes on environment for you first
MS Server 2008
Recent migration from exchange 2003
Exchange migration has been completed for about 3 weeks
Exchange 2003 is no longer available
Office 2007 is in use by all users
What happens is that a few random users when using outlook their contacs and calendar are no longer visible. They have not been deleted, just are not visible. If you go and list all the folders they do not show up in the list. They have not been accidentally moved into a subfolders. When in the individual sections of outlook, ie in contacts, any additional contact list are listed, just not the personal contact list that would be there if they were a new user. same is true for the calendar. The ways that users can still access them is if they go to and select open shared calendar\contact list and type in their username. it will immidiately open it up again, but it will not appear in the list of caledars in outlook. Users still recieve updates from their calendars. Users can still access their calendar from the home page.
If a user opens up OWA everything shows up correctly there. Unfortunately I dont believe this to be purely a client side issue. If I have the user log into another computer and setup outlook, the problem moves with the exchange account.
I have ran into this with several users and previously ended up having to remove and recreate their exchange mailbox. One of the interesting things that I have found is that if i use the Exchange power shell and export their account to a PST it does grab the calendar and contacts, but if I do it through outlook it does not get that information.
I originally thought that this was an effect of the exchange migration and hoped I had seen the last of it 1 week ago. Unfortunately I had another user with the problem crop up which means I may see this again on other users computers. I am hoping to come up with a solution that is better than what I have been doing.