Avast has installed something called "Grime Fighter" and it's taken over Scott's computer. What can he do? Leo says this is why he's not in favor of using third party antivirus software anymore. They give you a false sense of security and it can open up additional vulnerabilities. Leo suspects that Grime Fighter is not from Avast, but instead is pretending to be. At this point, the only thing you can really do is back up your data, format your hard drive, and reinstall Windows from a known good source. And if you must have an AVS, use Microsoft's own Windows Defender. It's fine for the job. But the reality is, your best hope is your own behavior.