Having bizarre issues with Firefox not opening or responding to anything I ask it to do. First it doesn't run when I hit the QA toolbar, it also doesn't run when I double click the shortcut or run as admin from the main C: folder.
The weird part is I can't reinstall because it does the same thing when I go in control panel to uninstall, it just idles and doesn't do anything. I managed to install Chrome (through Internet Explorer) after using a system restore point but FF is still doing the same things even after a restore point a month ago when I know everything was okay. I just want to reinstall FF, not sure if this is a compatibility issue or virus. The only thing I noticed yesterday was a sidebar ad on a website that doesn't have ads.

Things I've tried:
Restart
Restore point
Uninstall/Reinstall (can't)
Virus scan. Using Avast and did quick scans and specific scans to the Internet explorer and Firefox folders. No positive results.

I also had Internet Explorer crashing every time it ran until I used a restore point. I was getting error windows with no dialog in them too. I can use the internet and can even play PoE, it seems like Firefox specifically is causing issues from what I gather.
Running W7 btw.

This post was edited by TheGreatJohnJohn on Sep 5 2017 10:14am

Give your system a full scan with Malwarebytes ( https://www.malwarebytes.com/ ) as well. Avast usually doesn't pick up all spyware and adware.
It does sound like the system is or was either infected with something malicious, and/or has serious registry issues. After scanning with Malwarebytes, try running CCleaner: https://www.piriform.com/ccleaner/download

Edit: Added links

This post was edited by Arkhen on Sep 5 2017 10:23am

Did that and found no viruses, ccleaner didn't do anything as well. Ended up following a YT video after I finally got a window that had error dialog. Apparently manually removing every FF folder in the appdata folder did the trick, yet somehow CCleaner didn't do this automatically on a full system run? On Firefox now and everything seems OK. That was weird.
Still not understanding why a program wouldn't simply uninstall from the control panel.

RESOLVED

This post was edited by TheGreatJohnJohn on Sep 5 2017 10:53am

One of the folders in the appdata folder contains you Firefox profile. The profile is fairly easily corrupted or infected. Removing the Profile folder probably did the trick.

If you ever have problems with Firefox, this is usually your first best option...

http://forums.mozillazine.org/viewforum.php?f=38&sid=94e3a65fbd6b2d982cc56c3167a6f14d

Or so I thought...having the same problem except this time with IE. Every time I load it it crashes (has stopped responding). Using a second computer to post this since I can't access any browsers. I did manage to uninstall FF this time, but with IE crashing I'm out of options. It doesn't seem to be a FF exclusive problem, just some browser related issues. I can play PoE and even stream just fine, but I can't get any browsers to work properly. I'll try switching to Chrome for now, but I'm getting the feeling it might be a more core issue with files.

Things I've tried in addition to items in post #1:
Starting up browsers offline (LAN cable unplugged) they still crash.
Turning off Antivirus: There was an update just around the time this weird stuff happened and I got the suspicion it might be this, but nothing. Would uninstalling Avast be worth the time?
IE. Same issue.
Updating Drivers.

Moving on to Chrome and seeing how that works. I'm running out of patience with this one, anyone have any ideas to try before I resort to reformatting? I have an external to save stuff on but I already lost all my bookmarks.

This post was edited by TheGreatJohnJohn on Sep 6 2017 09:30am

Well, you can open a command prompt as Admin and type: sfc /scannow (space tween the sfc and the /scannow)

This will run Windows system file checker which will check for any corrupt system files.