I am running Windows 2000 SP3 on a home built AMD750. Almost every time I turn on my computer, I get the following message:Files that are required for Windows to run properly have been replaced by unrecognized versions. To maintain system stability, Windows must restore the orginal versions of these files. Insert your Windows 2000 CD now.I have done this numerous times to no avail. Sometimes I just cancel through the message. Any ideas?