Error – Error: The MSIX Application metadata expand request failed on all Session Hosts that it was sent to. Session Host: Azeus2pl1, Error: Error accessing virtual disk at ≤\\avdstrgeus2userprofile.file.core.windows.net\msix\vlc4.vhdx≥. (Code: 400)
Problem – you are able to see the error means you already know what is MSIX and how to use it with Azure virtual desktop. “The MSIX Application metadata expand request failed on all Session Hosts that it was sent to” is showing in MSIX package under Azure virtual desktop becasue the VHD file is not accessable from the session host.
Solution – Azure virtual desktop MSIX package allow you to add the application vhd\vhdx and assign it to application group so that user can access the application dynamicly. when you try to add vhd\vhdx the AVD check the UNC path (any file share path) from session host from the same hostpool and if its not reachable or if the session host dont have read permission on the vhd\vhdx file then you will face this error.
first thing i would suggest is to check if the UNC path is reachable and accessable from session host. you can login to any session host and try to access it. for testing you can create file share of any one of the session host and see if the AVD accepting the unc path.
Second and most common issue is permission on the vhd\vhdx file. make sure you have ready permission to session host or you can add read permission to everyone for testing and verify if the AVD is accepting the UNC path.
finally you will be able to see below screen once you fix the permission and share access.