|Not sure if 2010 retained the abiltiy, but on 2007:|
First, try a Diagnostic:
Running Microsoft Office Diagnostics from the Start Menu
Click on the Start button
Click All Programs
Click Microsoft Office folder
Click Microsoft Office Tools
Click Microsoft Office Diagnostics
Click Run Diagnostics
If you do not have the Diagnostic program, then try running a repair from the Control Panel, Add or Remove.
Click on the Start Button
Click on Control Panel
Click on Add or Remove Programs
Scroll down to the Microsoft Office or Word entry and select the entry,
there should be two buttons on the right, select the one that says: Change
It should now offer you three choices, select: Repair
See if that helps.
You may need the original install media when doing a repair.