AppLocker, which is built in to Windows 7 Enterprise and later, prevents unknown programs from running unless installed or otherwise pre-cleared by an admin first. This is increasingly necessary because even antivirus companies are publicly saying that antivirus provides little protection against current malware. Rather than attempt to enumerate what's bad, application whitelisting technologies like AppLocker enumerate what's good, and deny everything else. This turns out to be less difficult than it sounds.
If a program won't run and you are directed to this page
When a program is blocked by AppLocker, Windows will pop up the message shown at right. The "More information" link goes to the web page you are reading now.
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