WindowsApp cannot be launched on a thin client device when UWF (write filter) is enabled.

Question

I am connecting to Azure Virtual Desktop using a remote desktop app from an HP thin client device.

Thin client device OS: Windows 10 IoT Enterprise LTSC 2021 (Build 21H2)

 

The remote desktop app will no longer be supported by Microsoft in March next year, so we are in the process of switching to WindowsApp.

https://techcommunity.microsoft.com/blog/Windows-ITPro-blog/prepare-for-the-remote-desktop-client-for-windows-end-of-support/4397724

 

We installed WindowsApp on a thin client device for verification purposes, but WindowsApp does not start when UWF (write filter) is enabled.

*If UWF is disabled, WindowsApp will start.

*HP's Write Manager app is used to control the enable/disable status of the write filter, but it appears that UWF is actually running in the background.

 

When I contacted HP support, they told me to exclude WindowsApp-related folders from the write filter, so I excluded the following folders, but WindowsApp still does not start.

 

C:\Program Files\WindowsApps

C:\Users\username\AppData\Local\Packages\MicrosoftCorporationII.Windows365_8wekyb3d8bbwe

C:\Users\username\AppData\Local\Microsoft\WindowsApps

C:\Program Files (x86)\Microsoft\EdgeWebView

 

I would like to be able to launch WindowsApp even when the write filter is enabled. Could you please advise me on how to do this?

Answer 1

Hello T.I,
You’re seeing this because UWF blocks the UWP framework’s writes to its package, per-user state and registration DB. You need to carve out those paths and keys so the Remote Desktop app can install and run under UWF

# Exclude app package and registration DB
uwfmgr.exe file filter add-exclusion "C:\Program Files\WindowsApps"
uwfmgr.exe file filter add-exclusion "C:\ProgramData\Microsoft\Windows\AppRepository"
# Exclude per-user LocalState (repeat per account as needed)
uwfmgr.exe file filter add-exclusion "C:\Users\*\AppData\Local\Packages\*\LocalState"
# Exclude Appx service registry hives
uwfmgr.exe registry filter add-exclusion "HKLM\Software\Microsoft\Windows\CurrentVersion\Appx"
uwfmgr.exe registry filter add-exclusion "HKLM\SYSTEM\CurrentControlSet\Services\AppXSvc"
# Commit and reboot
uwfmgr.exe commit-changes
Restart-Computer

After reboot - with UWF still on - the Store Remote Desktop (WindowsApp) should launch normally. If it still fails, check Event Viewer > Applications and Services Logs > Microsoft > Windows > AppxDeployment-Server for any “access denied” entries and add those paths/keys to your exclusions.