This policy setting allows you to configure whether or not to display AM UI to the users. If you enable this setting AM UI wont be available to users. Counter Measure: Configure this setting depending on your organizations requirements. Potential Impact: Users are able to access the AM UI during the boot process. Fix: (1) GPO: Computer Configuration\Administrative Templates\Windows Components\Windows Defender\Client Interface\Enable headless UI mode (2) REG: HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows Defender\UX Configuration!UILockdown