What's the difference between the Unread Messages view and the Unread Mail search folder in Microsoft Office Outlook 2003?
A search folder is a persistent view of items meeting certain criteria in specified folders. The concept has existed for some time in Outlook add-ons, but Outlook 2003 is the first version to incorporate the concept into the basic product.
The main difference between a view and a search folder is that a view shows items in one folder, whereas a search folder can display items in multiple mail folders. (Outlook 2003 supports search folders for mail only, but future versions might extend the concept to other types of folders.) So the Unread Messages view shows unread items only in the current folder, but the Unread Mail search folder shows unread items in all the folders that the search encompasses.