I have just finished migrating my users to a new Exchange 2010 server from an Exchange 2003 server. Many of them have now reported an intermittent problem with their inbox not displaying contents. The folder list still displays the number of unread messages, but when you click on the inbox it says "no items to display". The items are viewable for a short time when an email is received, but (after an undetermined time period) if the user navigates away from the inbox and back again it display "no items to display". I have run all updates to Office (2007) and Windows (XP) to no avail. Any suggestions?