This policy setting allows you to manage whether a check for new virus and spyware definitions will occur before running a scan.
This setting applies to scheduled scans as well as the command line "mpcmdrun -SigUpdate", but it has no effect on scans initiated manually from the user interface.
If you enable this setting, a check for new definitions will occur before running a scan.
If you disable this setting or do not configure this setting, the scan will start using the existing definitions.
|Registry Path||Software\Policies\Microsoft\Windows Defender\Scan|