User Configuration > Administrative Templates > Microsoft Office 2016 > Security Settings > Trust Center > Trusted Catalogs
User
HKCU\software\policies\microsoft\office\16.0\wef\trustedcatalogs
This policy setting allows users to control all the Trusted Shared Folder Catalogs when other policy settings in the Trusted Catalogs folder are set by policy. Note: This setting only applies to Version 2308 or later of Office. If you enable this policy setting, users can set their own Trusted Shared Folder Catalogs including the Default Shared Folder location. Shared Folder Catalogs defined by policy will not be used. If you disable this policy setting, then all Trusted Shared Folders Catalogs are policy controlled. If you do not configure this policy setting but do configure other policy settings in the Trusted Catalogs folder, the Trusted Shared Folder Catalogs are policy controlled. If you do not configure this policy setting or any other policy setting in the Trusted Catalogs folder, users can set their own Trusted Shared Folder locations.