Unable to complete quick scan. HELP!

I need help. I am unable to complete a quick scan. It goes to 86% then freezes - twice. Already added malwarebytes and ran it. Eliminated 1 critical threat and 16 regular threats. Prior to that I was getting the blue screen of death! Originally downloaded Mozilla Firefox and it included unwanted software (ads) that I said no to and it somehow got downloaded anyway. Removed firefox from computer after running malwarebytes, thinking firefox may have something to do with the incomplete scan. I’m in the dark here. Tried a full scan last night and it only got to 35%. HELPPPPPP. I’m lost as to how to complete this. I have Avast free. I know…what should I expect for free? Any advise? Running on Windows 7.

Attach Farbar Recovery Scan Tool logs … https://forum.avast.com/index.php?topic=53253.0

I cannot operate Malwarebyte “Settings”. Program does not respond. Is that something I only get if I PAY for the upgrade?

No. Available in all versions :slight_smile: