If You are having problems where the Inbox in Outlook 2011 is not updating properly, You can clean out the inbox cache and let It resynchronize by doing this:
- Right-click or Control-click the Inbox
- Select Folder Properties
- Click the Empty button to empty the cache.
- You can also select the account itself and empty the cache for all of your folders.
This will work with Entourage 2008 also.