This policy setting allows you to configure definition updates on startup when there is no antimalware engine present.If you enable or do not configure this setting definition updates will be initiated on startup when there is no antimalware engine present.If you disable this setting definition updates will not be initiated on startup when there is no antimalware engine present.
Policy path:
Windows Components\Windows Defender\Signature Updates
Scope:
Machine
Supported on:
At least Windows Server 2012 Windows 8 or Windows RT
Registry settings:
HKLM\Software\Policies\Microsoft\Windows Defender\Signature Updates!DisableUpdateOnStartupWithoutEngine
Filename:
WindowsDefender.admx