Alan just installed Windows 10 on a few computers and wants to know if there's any reason to install a third party antivirus program with it. Leo says that Google has done a study about this, and they've found that most security experts believe antivirus software gives a false sense of security and doesn't guard against zero day exploits, which are the real threat now.
The most important thing Alan can do is make sure his system is up to date all the time. Set Windows to auto update. On top of that, Windows now has a very good antivirus utility called Windows Defender. So there's no real reason to run a third party antivirus program now. But in addition to keeping Windows updated, he'll have to have Flash, Shockwave, and any other third party utility that automatically runs within the browser updated. Next, he should use two factor authentication, especially with his email account. He should also run as a limited or standard user, not an administrator. A password vault like LastPass will allow him to have secure and unique passwords as well.