We all know Windows Defender as a free integrated antivirus solution by Microsoft. We also know that its latest versions provide decent antimalware protection, so average Web surfers don’t really need additional third-party programs for protection (if Windows Defender is configured properly).

Protect Your Computer With This Windows Defender's

Besides integrated antivirus modules and malware scanning algorithms (enabled by default), Windows Defender also has a very useful hidden feature to protect the users from potentially unwanted programs (PUP) and applications (PUA). Today we are going to tell you, how to enable this function and enhance your security.

For those, who does not know what exactly unwanted programs do and what they are, here is a quick explanation: it is software which is not a virus, does not have malicious code, and cannot harm your system directly, but still has a bad reputation and may open loopholes for other cyber threats. For example:

  • Unnecessary programs that come in bundles with useful freeware (usually installed automatically without user’s consent).
  • Apps that inject ads into browsers change homepages, mess all browser settings up, switch your default search engine.
  • Various optimization tools and registry cleaners created by no-name companies. Such programs always find dozens of threats and errors that must be neutralized with the “Pro” version of the product, which is not given for free, of course.

We will cover two methods that can be used to enable hidden Windows Defender resources – the first one requires some Windows Registry digging, while the second one requires some typing in Windows PowerShell.

Activate anti-PUP protection in Windows Defender using PowerShell

According to Microsoft, the anti-PUP feature is only available in Windows Defender for Windows 10 Enterprise. Whereas in fact, it is possible to activate the feature in Home or Pro editions. The easiest way to do that would be with Windows PowerShell:

  • Run PowerShell as administrator (right click on the Start Menu button or press Win+X and select the mentioned option from the list).
  • Type Set-MpPreference -PUAProtection 1 and hit Enter.
Activate anti-PUP protection in Windows Defender using PowerShell
  • The anti-PUP feature in Windows Defender is now enabled (in order to deactivate it, you just need to use the same command in Windows PowerShell but type “0” instead of “1”).

When this feature is active, all attempts to run or install potentially unwanted programs will be blocked, and you will see a warning message from Windows Defender.

Warning message from Windows Defender

Information in the program’s log will be presented in the form that looks like this (affected items and folders will be different):

Enable anti-PUP protection in Windows Registry

You can activate hidden features of Windows Defender by adding a few things in Windows Registry. Open the registry by pressing Win+R and typing regedit in the window to appear.

Go to the directory HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows Defender and create a new DWORD value. Change its name to “PUAProtection” and set its value data to “1”.

You will also have to create another DWORD in the directory  HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows Defender\MpEngine (if that directory is missing, create a subfolder and name it “MpEngine”). The name of the newly created DWORD must be MpEnablePus. Set its value data to “1” as well.

Enable anti-PUP protection in Windows Registry

When it is done, you can close Windows Registry – from now on your Windows Defender will be blocking all potentially unwanted programs and apps.