I cannot access my Microsoft help files though any Office application.

Facts:
- Windows XP
- Office 2007
- Works for other user accounts on the same machine
- Checked file extensions - HTML, HTM, XHTML and XML all are associated with IE
- Tried to repair Office and rebooted machine - no luck
Note: If you click on the links in the sidebar in the Help dialog box, the pages display correctly. It just does not display when initially opening or while searching.
