What troubleshooting steps have you taken?
Questions about your environment:
Have all released Microsoft patches for Office been applied to the client?
Do you use virus scanner with updated definition files?
Do you use a mixed version office environment, for instance, Office 2007
Standard with Access or Project 2000 or 2003? I know that if Office Standard
2003 is installed and then Access 2000 is installed after it that the
Spellcheck dictionary files are overwritten with the older version causing
Word to crash immediately when opened.
Have you tried creating a new profile for the user and try duplicating that
issue, or have another user without the issue login to the PC with the issue
and see if you can duplicate it?
Have you tried renaming any files in the xlstart folder for excel and the
normal.dot for word to see if it resolves the issue?
Are macros used in your environment?
Is the Office Document
Converter pack installed?
I know this is not a solution, but I hope this helps identify the problem.