Can't edit registry and Malwarebytes won't even open...

I'm running Windows 8.1 Pro, activated via KMS.

So, yesterday I started getting these notifications saying my license is about to expire—like, I've only got a month left.
I figured, whatever, I'll just deal with it tomorrow or sometime later this week.

But since I'm working in Unreal Engine 4 on some stuff for Android, I had to get the Android SDK Development tools (or whatever 😁 ) installed, but it keeps failing because it says I'm missing Visual Studio.
I actually went ahead and reinstalled Visual Studio yesterday, even though I was pretty sure I already had it, maybe just an older version.
Just mentioning the Visual Studio thing in case it has anything to do with these other issues:

- I can't get into regedit at all, whether I try through the run command or by clicking the .exe directly.
- Even Malwarebytes won't open so I can run a scan, not even when I'm in Safe Mode.

It’s not even giving me an error code or anything; it's just... nothing happens.

AVG flagged five viruses overnight, and even after I cleared them, nothing changed.
I tried uninstalling Visual Studio too, but still no luck.

I don't really browse the web much; I mostly just download textures and stuff since I do 3D modeling and I'm working on an Android game.

Do you think the license issue is waking my PC up, or did I maybe catch something sketchy that's blocking these programs from running?

The computer usually runs totally fine otherwise.

I know we aren't supposed to talk about piracy on this forum—rules are rules, right? But honestly, using a KMS tool to activate Windows isn't actually related to the issue you're facing here. You should probably try running a Windows repair instead and see if that clears things up...

I heard from a few people that this is actually a pretty common issue; I guess in like 90% of cases, it’s just a virus blocking you from opening anything related to Malwarebytes or even regedit.

There are a couple of ways to fix it—either try using the Malwarebytes Chameleon tool, which I honestly had no clue about until yesterday (it basically unblocks mbm.exe from the Trojan), or maybe just manually rename mbm.exe to something else. You could also try using a couple of other antivirus programs.

If none of that works... well, I guess you're looking at a system restore or a full reinstall.

Fixed it! I ran Chameleon Malwarebytes via CMD Malwarebytes and it caught 40 different Trojans.

Everything's working smoothly now, including the registry and all that stuff.