Are you updating the definition file of malwarebytes/other scanners?
If you had them on your PC months/years ago and just using the old definition files that will not be very successful.
If you are running the latest definition files then the infection has a rootkit (or multiple) reinstalling the malware when you reboot.
Trying to find an neutralize an unknown infection over the internet is the proverbial needle-in-a-haystack, will probably just need to wipe and reinstall windows.
Only thing else I can suggest trying is open start menu and type "msconfig", then enlarge it and go to the "boot" tab and then take and post screenshots of what is in there and we can tell what to try to disable. This will not get rid of the virus, just keep it from automatically starting up.