When booting I press F8 and there is an option “Safe Mode with Command Prompt”, but when I select it, it says that if this is the first time you've seen this situation (that is, a blue screen, with English prompt information on it), please restart, and then something else, roughly meaning whether this function has been disabled, and also if it happens like this every time then check whether it has been infected by a virus, and so on. It's running Windows XP SP2, very strange indeed. Asking an expert for guidance, thanks!~~~~~;)
