Windows File Protection in Win2000

I have been using win2000 on my Fujitsu Laptop for about 4 months and it has been working great until now. Whenever I start computer in the morning, I get a “Windows File Protection” messages and I am asked to insert the win2000 cd (this would be fine if it didn’t happen 14 times a day while I was trying to work). I checked out the event log, and the system log basically says “windows file protection” all the way down the list. The log reports that certain files were attempted to be replaced, but doesn’t tell me why. And for those of you who are going to suggest that I format the hard drive and re-install, I have already done that and it didn’t make a difference. Can anyone out there help me?
Thanks.