MS Office: Trust Center - Trusted Locations

Trusted Locations is a Trust Center list of directories on hard disks and locations on file shares where stored files are trusted.

The list of trusted locations is maintained in the registry under HKEY_CURRENT_USER/Software/Microsoft/Office/{version}/{name}/Security/Trusted Locations (for example HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Excel\Security\Trusted Locations)