The Windows Security app is a client interface on Windows 10, version 1703 and later. See the Windows Security article for more information on other Windows security features that can be monitored in the app. This will significantly lower the protection of your device and could lead to malware infection. It might also prevent Microsoft Defender Antivirus from enabling itself if you have an old or outdated third-party antivirus, or if you uninstall any third-party antivirus products you might have previously installed.

If you do disable the Windows Security app service, or configure its associated Group Policy settings to prevent it from starting or running, the Windows Security app might display stale or inaccurate information about any antivirus or firewall products you have installed on the device.

These are disabled automatically when a third-party antivirus or firewall product is installed and kept up to date. Disabling the Windows Security app service does not disable Microsoft Defender Antivirus or Windows Defender Firewall.

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