You can use the Microsoft Database Utility that is stored in Microsoft Office 2008/Office/ to compact and back up the Microsoft Entourage 2008 for Mac database.
If an Microsoft Exchange account is used from both Entourage and Outlook, compacting or rebuilding the Entourage database could cause duplication of the user's messages. To avoid duplicating a user's messages, delete the Microsoft Exchange account in Entourage before you compact or rebuild the Entourage database. Then re-create the Microsoft Exchange account in Entourage after compacting or rebuilding of the database is complete.
Compact and back up the database
Quit all Office applications, including Entourage and Office Reminders.
Do one of the following:
In the Microsoft Office 2008/Office folder, double-click the Database Utility application.
Hold down the OPTION key and open Entourage.
In the Database Utility dialog box, click the name of the database that you want to compact and back up.
Click Compact database, and then click Continue.
Follow the instructions in the dialog box.
When you compact the Entourage 2008 database, this process creates a backup copy of the database, just as the rebuilding process does.
