Here is a useful tool that will work.
"If used on users that have EFS encrypted files, and the system is XP, all encrypted files for that user will be UNREADABLE! and cannot be recovered unless you remember the old password again. If you don't know if you have encrypted files or not, you most likely don't have them. (except maybe on corporate systems)"
The how-to is near the top. The download is at the bottom of the page. The how to is kind of hard to follow, if you have any trouble just let me know where you get stuck and Ill try to help.