Configure additional sources for untrusted files in Windows Defender Application Guard.

This policy setting allows you to configure additional sources for untrusted files.
If you enable this setting, you must select one or more of the following:
1. Removable media: Files opened or copied from removable media will always open in Windows Defender Application Guard.

2. Network shares: Files opened or copied from network shares will always open in Windows Defender Application Guard. If you want to explicitly trust a network location and prevent files from that location from opening in Application Guard, use one of the Network Isolation policies.

3. Files with Mark of the Web (MotW): Files stamped with MotW will always open in Windows Defender Application Guard.

If you disable or don't configure this setting, only files downloaded from Application Guard for Microsoft Edge will open in Application Guard for Microsoft Word, Excel, or PowerPoint.

Supported on: Windows 10 Enterprise, Windows 10 Education, or later

Removable media
Registry HiveHKEY_LOCAL_MACHINE
Registry PathSOFTWARE\Policies\Microsoft\AppHVSI\FileTrustOrigin
Value NameFileTrustOriginRemovableMedia
Value TypeREG_DWORD
Default Value1
True Value1
False Value0
Network shares
Registry HiveHKEY_LOCAL_MACHINE
Registry PathSOFTWARE\Policies\Microsoft\AppHVSI\FileTrustOrigin
Value NameFileTrustOriginNetworkShare
Value TypeREG_DWORD
Default Value1
True Value1
False Value0
Files with Mark of the Web
Registry HiveHKEY_LOCAL_MACHINE
Registry PathSOFTWARE\Policies\Microsoft\AppHVSI\FileTrustOrigin
Value NameFileTrustOriginMarkOfTheWeb
Value TypeREG_DWORD
Default Value1
True Value1
False Value0

apphvsi.admx

Administrative Templates (Computers)

Administrative Templates (Users)