Protect your PC from potentially unwanted applications

Applies to: Windows 10

Potentially unwanted applications (PUA) are a category of software that can cause your machine to run slowly, display unexpected ads, or at worst, install other software which may be more harmful or annoying.

Windows Security has reputation-based protection that can help protect your PC from potentially unwanted applications. Potentially unwanted app blocking was first introduced in Windows 10 May 2020 update, and is turned off by default.

How do I turn it on?


To turn on potentially unwanted app blocking go to Start  > Settings  > Update & Security > Windows Security > App & browser control > Reputation-based protection settings

There you'll find a control that lets you turn potentially unwanted app blocking on, and select if you want to block apps, downloads, or both. 

The potentially unwanted app blocking control in Windows 10.

We recommend that you turn this feature on, and that you enable both block apps and block downloads.

  • Block downloads looks for PUA as it's being downloaded, but note that it only works with the new Microsoft Edge browser.
  • Block apps will detect PUA that you've already downloaded or installed, so if you're using a different browser Windows Security can still detect PUA after you've downloaded it.