Avast automatically updated itself earlier this week and my Windows start acting strange.
Everything starts up ok but after a while things stop responding one by one, browser not responding, cannot close existing program, cannot start new program, cannot open task manager, and finally cannot shutdown. I have to power off my notebook every time.
At first I did not know it was Avast and tried to fix Firefox, Windows, damaging it along the way. Then I found out if I disable Avast, the problem goes away. I tried re-install with the latest download today but still have the same problem. Too bad I have to uninstall it for good after enjoy using it for several years without any issue.