Enable Download to Host from Windows Defender Application Guard Microsoft Edge session in Windows 10
Microsoft Edge is a new web browser that is available across the Windows 10 device family. It is designed for Windows 10 to be faster, safer, and compatible with the modern Web.
Microsoft Edge running in Application Guard provides the maximum level of protection from malware and zero day attacks against Windows. Windows Defender Application Guard for Microsoft Edge is a lightweight virtual machine that helps isolate potentially malicious website activity from reaching your operating systems, apps, and data.
There is no persistence of any cookies or local storage when an Application Guard window is closed in Microsoft Edge.
Three core features of Windows Defender Application Guard:
- Isolated Browsing - Windows Defender Application Guard uses the latest virtualization technology to help protect your operating system by creating an isolated environment for your Microsoft Edge session.
- Help Safeguard your PC - Windows Defender Application Guard starts up every time you visit a non-work-related site to help keep potentially malicious attacks away from your PC.
- Malware Removal - Any websites you visit, files you download, or settings you change while in this isolated environment are deleted when you sign out of Windows, wiping out any potential malware.
Starting with Windows 10 build 17120, the Windows Defender Application Guard (WDAG) Team has introduced new improvements for users to have a better experience. One of the items users voiced in the Feedback Hub was an inability to “download files from within WDAG” to the host. This created an inconsistent experience for Edge overall as downloaded files were stuck inside the container. In build 17120, users can now turn on a feature to download files from their WDAG Microsoft Edge browsing session onto the host file system.
After this policy (feature) is enabled, users can download files from their Windows Defender Edge session to their Downloads folder and open all files on the host. The files from Application Guard will be saved in a folder called Untrusted Files nested inside the Downloads folder. This folder is created automatically when the user first downloads a file from Application Guard after enabling the policy.
Notes:
- This feature is off by default.
- Users will need to assess the files they downloaded and assume any risks of opening on the host.
Requirements:
This tutorial will show you how to enable or disable the ability to download files from within a Windows Defender Application Guard Microsoft Edge session to the host for all users in Windows 10 Pro and Windows 10 Enterprise.
You must be signed in as an administrator to enable or disable the ability to download files from within a Windows Defender Application Guard Microsoft Edge session to the host operating system.
CONTENTS:
- Option One: Enable or Disable Download to Host from WDAG Microsoft Edge session in Local Group Policy Editor
- Option Two: Enable or Disable Download to Host from WDAG Microsoft Edge session using a REG file
EXAMPLE: Download to host from Windows Defender Application Guard Microsoft Edge session enabled and disabled

OPTION ONE
Enable or Disable Download to Host from WDAG Microsoft Edge session in Local Group Policy Editor
1. Open the
Local Group Policy Editor.
2. Navigate to the location below in the left pane of the Local Group Policy Editor. (see screenshot below)
Computer Configuration > Administrative Templates > Windows Components > Windows Defender Application Guard

3. In the right pane of
Windows Defender Application Guard in Local Group Policy Editor, double click/tap on the
Allow files to download and save to the host operating system from Windows Defender Application Guard policy to edit it. (see screenshot above)
4. Do
step 5 (enable) or
step 6 (disable) below for what you would like to do.
5. To Enable Download to Host from WDAG Microsoft Edge session
A) Select (dot)
Enabled, click/tap on
OK, and go to
step 7 below. (see screenshot below)
6. To Disable Download to Host from WDAG Microsoft Edge session
A) Select (dot)
Not Configured or
Disabled, click/tap on
OK, and go to
step 7 below. (see screenshot below)
Not Configured is the default setting.

7. Close the Local Group Policy Editor.
8. Restart the computer to apply.
OPTION TWO
Enable or Disable Download to Host from WDAG Microsoft Edge session using a REG file
The downloadable .reg files below will add and modify the DWORD value in the registry key below.
HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\AppHVSI
SaveFilesToHost DWORD
(delete) = Disable
1 = Enable
1. Do
step 2 (enable) or
step 3 (disable) below for what you would like to do.
2. To Enable Download to Host from WDAG Microsoft Edge session
A) Click/tap on the Download button below to download the file below, and go to
step 4 below.
Enable_SaveFilesToHost_in_Windows_Defender_Application_Guard_Edge_session.reg
Download
3. To Disable Download to Host from WDAG Microsoft Edge session
This is the default setting.
A) Click/tap on the Download button below to download the file below, and go to
step 4 below.
Disable_SaveFilesToHost_in_Windows_Defender_Application_Guard_Edge_session.reg
Download
4. Save the .reg file to your desktop.
5. Double click/tap on the downloaded .reg file to merge it.
6. When prompted, click/tap on
Run,
Yes (
UAC),
Yes, and
OK to approve the merge.
7. Restart the computer to apply.
8. If you like, you can now delete the downloaded .reg file.
That's it,
Shawn