Nick doesn't want to update to the Windows 10 1803 update. How can he keep from updating? Leo says that he can defer it by telling Windows he's on a metered connection (in network settings), but ultimately, he's going to have to bite the bullet. Leo says that he can save the update on a thumb drive, but Avast could be causing issues with the update. Nick should check out this article on windowscentral.com for common problems and fixes.
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.