My experience with a similar issue was as suggested by Firefox. Shut down your client and start it in Safe Mode. It should startup OK in Safe Mode (other than your display may render at a low resolution). Once in Safe Mode you should be able to run Malwarebytes with no issues. In my case Malwarebytes ran a full scan, found the cause of my clients misbehavior and removed them (yes, there were several). I shut down, rebooted in Normal Mode and ran Malwarebytes again (full scan(to be certain everything was cleaned)). Hope one of these solutions works for you. Let us know how it works out.