Ok so a couple hours ago this happened.  I was just browsing the internet, checking my youtube, lcpdfr, etc. Then when I exited chrome, all my crap was gone. The desktop was clean, the file explorer wouldn't let me see any of my files, and whenever I clicked on anything my computer just froze. So I quickly shut my pc down and left it for a couple of minutes. I tried to sign in but windows took 5 minutes to accept my sign-in and then my computer was doing the same thing again. I kept trying for literally 10 times and then it worked and everything was fine. But when I opened chrome or any other browser I got one of those browser virus's where whenever you open a new tab new windows pop up with ads or fake updates. I think I got rid of that now but I'm kinda freaking out. Is there any free software I can use to check my pc for virus's and stuff, other than the default Microsoft stuff?

 

Also I made sure I backed up everything important

Sounds like you got malware. Adaware was good. I haven't used it recently. Last time I did it was bloated for my P4 machine. It got rid of the malware. But uninstall it once your done or keep it if your PC doesn't have a hissy fit.

 

Malwarebytes is always a free, trusted malware checker. 

 

Perhaps it's not malware, although I can't think of any plausible alternative off the top of my head. Faulty RAM? Try reseating the ram? 

Ok so a couple hours ago this happened.  I was just browsing the internet, checking my youtube, lcpdfr, etc. Then when I exited chrome, all my crap was gone. The desktop was clean, the file explorer wouldn't let me see any of my files, and whenever I clicked on anything my computer just froze. So I quickly shut my pc down and left it for a couple of minutes. I tried to sign in but windows took 5 minutes to accept my sign-in and then my computer was doing the same thing again. I kept trying for literally 10 times and then it worked and everything was fine. But when I opened chrome or any other browser I got one of those browser virus's where whenever you open a new tab new windows pop up with ads or fake updates. I think I got rid of that now but I'm kinda freaking out. Is there any free software I can use to check my pc for virus's and stuff, other than the default Microsoft stuff?

 

Also I made sure I backed up everything important

I use Malwarebytes and avast!

Well, good luck.