Policy
Do not open files in unsafe locations in Protected View
This policy setting lets you determine if files located in unsafe locations will open in Protected View. If you have not specified unsafe locations, only the "Downloaded Program Files" and "Temporary Internet Files" folders are considered unsafe locations. If you enable this policy setting, files located in unsafe locations do not open in Protected View. If you disable or do not configure this policy setting, files located in unsafe locations open in Protected View.
a4497cc89bceL_DoNotOpenFilesInUnsafeLocationsInProtectedViewRegistry
Copy registry mappings
HKCU\software\policies\microsoft\office\16.0\word\security\protectedview\disableunsafelocationsinpv (enabled) = 1
HKCU\software\policies\microsoft\office\16.0\word\security\protectedview\disableunsafelocationsinpv (disabled) = 0Policy notes
This policy setting lets you determine if files located in unsafe locations will open in Protected View. If you have not specified unsafe locations, only the "Downloaded Program Files" and "Temporary Internet Files" folders are considered unsafe locations. If you enable this policy setting, files located in unsafe locations do not open in Protected View. If you disable or do not configure this policy setting, files located in unsafe locations open in Protected View.