Grimefighter problem

I reinstalled Avast aintivirus and with that also got grimefighter. The problem is that i dont want the function so i havent paid for it.
Now when i start my computer grimefighter starts and asks me to login (where i dont have a user) i choose to reboot to get to windows, but when i reboot i get back to grimefighter. I cant access my computer!
I tried in BIOS settings (windows 8) to change the order or bootingalternatives and even took it away, but i either cant boot my computer at all Or i only end up getting back to grimefighter.
This affects my work AND schoolwork pretty bad! Does someone know if I can remove without being able to access windows?
This is a pretty annoying problem.

https://forum.avast.com/index.php?board=63.0

that means you are posting in wrong forum section … and Asyn gave you link to GrimeFighter forum section