The Windows 10 May 2019 Update contains a new tamper protection feature, also known as Windows Defender Antivirus. Tamper Protection is off by default and Windows Security says «your device may be vulnerable» if you don’t turn it on.
What is Tamper Protection in Windows 10?
According to Microsoft, Tamper Protection «helps prevent critical Defender antivirus protection settings, including real-time protection and protection in the cloud, from being modified by malicious applications.» In other words, it is more difficult for malware running on your computer to disable real antivirus protection and other features.
You can still configure the settings yourself using the Windows Security app. In fact, once you enable Tamper Protection, you shouldn’t notice anything else. That’s why we recommend enabling it.
Note that tamper protection only applies to Windows security settings. If you are using a third party antivirus, it will not protect the settings of that antivirus. Some third-party antivirus programs have similar built-in «tamper protection» features to protect their settings.
Protected options include real-time protection, cloud-based protection, IOfficeAntivirus (IOAV), behavior monitoring, and removal of security updates. Applications cannot change these settings using mobile device management and other enterprise solutions, command-line options, group policy, the Windows registry, and various other security-enabled methods.
How to enable tamper protection
This setting is included in the Windows Security app. To open it, search the Start menu for Windows Security and click the Windows Security shortcut, double-click the Windows Security Shield icon in the notification area (taskbar), or go to Settings > Update & Security > » Windows Security» > «Open». Windows security.
You may be prompted to enable tamper protection. You can just click «Enable» to turn it on.