The folder window is the left most column in Entourage. New in Entourage 2008, your default account will be listed at the top of the window. In previous versions, folders “On My Computer” (for POP accounts) was always on top followed by IMAP and Exchange accounts. If you use an Exchange or IMAP account as your default account, the folders “On My Computer” will drop to the bottom right above Mail Views. Mail Views position . . .
Continue Reading: Setting the Folder window in Entourage 2008