There should be a sticker on the bottom of your PC saying which operating system it has.
Have you tried tapping the F8 key when booting up? That should help you get into safe mode.
If it works, click on safe mode.
Once in safe mode (it may take awhile 3 minutes to maybe even 1/2 hr to reach the welcome screen depending on how damaged the operating sytem is....just let it run)
try doing a system restore back to before your problem.
Here is how to do a system restore:
See if that gets your laptop back up and running again. Let us know ok?
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