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Does the Safe Mode menu not even allow you to go to Command Prompt? If it does, type sfc /scannow and hit Enter. You will need your XP CD in the drive so the System File Checker can expand fresh copies of missing files. If you have a CD it's probably best to run the first Repair option but if you don't have a disk or can't borrow one, you're in trouble. As with all kernels, that one is in the very heart of the whole darned nut!