Allow Cortana

This policy setting specifies whether Cortana is allowed on the device.
 
If you enable or don't configure this setting, Cortana will be allowed on the device. If you disable this setting, Cortana will be turned off.
 
When Cortana is off, users will still be able to use search to find things on the device.

Supported on: At least Windows 10 Server, Windows 10 or Windows 10 RT

Registry HiveHKEY_LOCAL_MACHINE
Registry PathSOFTWARE\Policies\Microsoft\Windows\Windows Search
Value NameAllowCortana
Value TypeREG_DWORD
Enabled Value1
Disabled Value0

search.admx

Administrative Templates (Computers)

Administrative Templates (Users)