User Configuration > Administrative Templates > Microsoft Office 2016 > Security Settings
User
HKCU\software\policies\microsoft\office\16.0\common\security
This policy setting allows you configure if the document properties are encrypted. This applies to OLE documents (Office 97-2003 compatible) if the application is configured for CAPI RC4. If you enable this policy setting, the document properties will be encrypted. If you disable or do not configure this policy setting, the document properties will not be encrypted.