User Configuration > Administrative Templates > Microsoft Office 2016 > Security Settings
User
HKCU\software\policies\microsoft\office\16.0\common\security\labels
This policy setting controls whether the Microsoft Azure Information Protection add-in can be used rather than the default of built-in labeling to view and apply sensitivity labels in Office apps. It applies only to subscription versions of Office, such as Microsoft 365 Apps for enterprise. If you enable this policy setting and the Microsoft Azure Information Protection unified labeling client is installed, the add-in from that client replaces the default labeling built into Office apps. If you disable this policy setting or don’t configure it, the default labeling experience that’s built-in for Office apps is used to view and apply sensitivity labels. For more information about this setting, see https://go.microsoft.com/fwlink/p/?linkid=2207430.