Topic
This article addresses the error received when trying to connect to Virtual Desktop or Remote App from a Windows 11 device using the Windows App desktop application.
Audience
Solution
If you try to connect to Virtual Desktop or Remote App using the Windows App desktop application, you may encounter the below error:

To resolve this issue, install the Windows 11 out-of-band update from Microsoft. The update can be found here: https://www.catalog.update.microsoft.com/Search.aspx?q=KB5077744
Be sure to select the proper OS version (Windows 11 24H2 or 25H2) and architecture (amd64 or arm) for your particular device. If you are unsure, open Settings > System > About > and look at System Type. If it says "64-bit operating system, x64-based processor", it's an amd64; if it says "64-bit operating system, ARM-based processor", it's an arm processor.
Once downloaded, run the application and allow the device to restart. The Windows App should then connect successfully.
Alternately, you can use the Virtual Desktop Web Portal here: https://windows.cloud.microsoft/