I have this problem with Avast Secure Browser, long ago. It suddenly made everything slow, specially the internet pages, then I open the Administrator and I saw that avast was taking all the memory of the computer, so I followed some instructions to fix all avast by the configuration part in the app. I also unstilled the avast secure browser because it was a pain with facebook. So I open control panel / programs and uninstall the thing
the weird thing is that, when I opened the Administrator to see all the programs that works on second plane... there it was!!! Avast Secure Browser is still working...
How can I erase it completelly from my lap?
(sorry, for my bad english)