Alan wants to know if an antivirus utility is any good anymore for malware. How about on a mobile device? Leo says that all too often, an antivirus leaves people more vulnerable because most malware is a zero day exploit. Antivirus can't stop users from themselves, either. All antivirus utilities have to hook themselves into the OS at a very low level and the virus can actually use that as a door to more exploits. So at the end of the day, an antivirus really is only of limited benefit.
Windows 10 comes with a decent free antivirus that's good enough. At the end of the day, Alan's best defense will be his own behavior. He should keep his PC updated, and shouldn't open attachments or click on links, especially from friends or coworkers. What about using Malware Bytes occasionally? Leo says he doesn't use it. It works, but it can also cause more damage and still won't protect him from what Malware Bytes doesn't take off. It, too, creates a false sense of security.