My browser on Windows is possessed by a demon. How to fix Windows and expel evil spirits?

Question

Windows

Hello.
A very terrible thing has been happening since December - the Internet disappears. The Internet does not disappear physically, but in Windows itself. Although I will not call it that, no ...
It all started with the fact that updates were installed. Some very fatal updates, on which I put all the main suspicions. So what's going on:
When I use a chromium browser (absolutely any!) It is rare, but noticeable, that the browser freezes. At first, a long loading of pages, which was not crowned with success, and then a complete brake that cannot be killed. No way. When trying to open a chrome friend from mozilla, firefox, this action fails. After that, neither chrome processes nor firefox can be killed, either by the task manager or by taskkill /f /im. The command line claims that no such processes exist. However, it is treated, in a rather painful way. Why? Because it’s impossible to shut down Windows normally after such a “case”, processes interfere with shutting down. Comes with a button. Only after a reboot, which lasts longer than usual, everything falls into place. I can use firefox, no such jambs have been noticed behind it, although I can’t say that a similar fate awaits me in it. Please help, friends! Maybe someone has the same thing, maybe they treated it somehow ...
Briefly on the parameters:
- OS: Windows 8.1
- Internet: adequate, you will not find fault with the operation of the router
- Computer: powerful, for modern games. we discard all problems related to the power of the computer
- License: Windows with a genuine license. Don't think that being a pirate you will write about the Windows license. It's funny.

Answer 1

Upgrade to ten people! And from scratch, perhaps!

Answer 2

The Internet does not disappear physically, but in Windows itself.

There is a suspicion that just the same Internet disappears "physically". In a sense, as an option, the duration of the session (connection) is limited by the provider, for example, at 24 hours, to combat "hanging connections", that is, the computer (and OS) remain connected to the router, the router itself is connected to the provider's network, and reconnection, which happens quite quickly (sometimes almost instantly), you may not notice (although it will be visible in the log).