|Hi Toni, first I would suggest unlocking the Caps key because in PC language it means you are shouting.|
Try tapping f8 on bootup and then select safe mode. In safe mode try to do a system restore back to when the PC worked fine.
If that doesn't work tap f8 on boot-up and then select repair my computer. If you don't see that message you may have to make a recovery CD, I don't know if you have a 32bit or 64bit operating system:
That should help you
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