Computer Won't Run Any Programs And System Restore Keeps Failing?

I'm writing this from a different computer because I can't even get onto the internet on mine.Pretty much all programs fail to run. When I double-click on the icon, I get the usual spinning "loading" circle and then nothing happens.When I try to open straight from a saved file, I get an error message. For example, whenever I try to open a word doc, I get this error message: "There was a problem sending the command to the program."Symantec Endpoint Protection has been turned off and every time I go to the Action Center to turn it back on, nothing happens. I get the usual message that asks if I want to allow the change and when I click "allow," nothing changes.I've done several system restores, even in Safe Mode, and they have all failed. System repairs have all failed too. Obviously, virus scans are out of the question and Windows Defender (one of the programs that actually will run) keeps telling me that there is no malicious software to be found on my system.

This all started yesterday afternoon. I was running Firefox as usual and had a word document open that I was typing in. I walked away from my laptop and when I came back, there were three pop-ups on the screen from a virus that I had just managed to get rid of several days before. I closed them out and was preparing to run Malwarebytes when my computer shut itself down suddenly. There haven't been any pop-ups or anything that would indicate that this is a virus. However, I tried the same fix that I used to remove the virus the first time (copying the Malwarebyes file 'mbam.exe' to the desktop and naming it as 'mbam.COM' so that it will open) but even that does not work. I've tried the regedit fix that I've found in forums here but that didn't work either.