The setting is stored in the Windows registry, so you will need to log
in to Windows as a user who has permission to modify the registry.
In Word 2007:
1. Press Alt+F11 to open the Microsoft Visual Basic Editor.
2. Either click on View | Immediate, or press Ctrl+G, to open the
Immediate window.
3. In the Immediate window, type:
Application.DisplayAutoCompleteTips = True
and press Enter.
4. Either click on File | Close and Return to Microsoft Word, or press
Ctrl+Q, to exit the Microsoft Visual Basic Editor.
You only need to do this once. Word should remember this setting
forever or until you change it.