User Configuration > Administrative Templates > Microsoft Word 2016 > Word Options > Security
User
HKCU\software\policies\microsoft\office\16.0\word\security\filevalidation
This policy setting allows you turn off the file validation feature. If you enable this policy setting, file validation will be turned off. If you disable or do not configure this policy setting, file validation will be turned on. Office Binary Documents (97-2003) are checked to see if they conform against the file format schema before they are opened.