Windows XP forum: "Cannot Access Windows Management Instrumentation software"

When I try to use the system information utility, I the the error message;

" Cannot access windows management instrumentation software. Windows management files may be moved or missing."

I have been searching the internet for three days straight trying to locate a "fix" for this error. I have tried everything from reinstalling my repository files to checking the services to be sure the necessary services are indeed installed and running. I have all but come to the conclusion that there is nothing I can do to fix this problem, short of reinstalling XP. The problem with that is the PC was a gift (and bought used, from a rent to own store) so I did not receive any of the software with this computer. To be quite honest I don't really want to spend the money to buy another copy of an operating system. There isn't anything wrong with the one I am currently running other than the error code. I have downloaded Karen's computer profiler from Download.com, which I might add is great, so the system information utility is rather useless to me now anyway.
However, I do need to know if running my system with this problem could cause other problems that I may not consider. How crucial is WMI to Windows XP? Could this be a symptom of something far worse? I would really like to fix this problem, but if it were left alone would it get worse? Any feedback would be greatly appreciated.