Get-LoggedOnUser broken within Windows Sandbox due to truncated ComputerName environment variable

[obuolinis]

Describe the bug
When run from within Windows Sandbox Get-LoggedOnUser fails with the following error message:
Exception calling "GetUserSessionInfo" with "1" argument(s): "The operation completed successfully"

To Reproduce
Steps to reproduce the behavior:

1. Run any PSADT package from within Windows Sandbox (tested on Windows 11 only)
2. You get the error during the Initialization stage in the console and/or in the log.

Toolkit Version:
Tested with 3.9.3

Powershell Version:
5.1

Additional context
This has been bugging me for quite some time already since I really love using Windows Sandbox as my PSADT package testing environment.
According to my investigation this is related to both Windows and Windows Sandbox design. The root cause is that Get-LoggedOnUser is calling GetUserSessionInfo CS function using Windows environment variable ComputerName as the name of the host:

PSAppDeployToolkit/Toolkit/AppDeployToolkit/AppDeployToolkitMain.ps1

Line 15811 in d04eda2

Write-Output -InputObject ([PSADT.QueryUser]::GetUserSessionInfo("$env:ComputerName"))

An actual computer name within Sandbox is a random GUID whereas ComputerName variable truncates it to 15 chars which is what breaks the function.

Fix Suggestion
This could possibly be a rather simple fix - you could be calling GetUserSessionInfo using DNSHostName property value of WMI class Win32_ComputerSystem rather than an environment variable. This property holds a full non-truncated computer name.
I'm not aware of any potential repercussions.

[AlkHacNar]

don't work with the 3.10.1 too, but you can fix/workaround it with you change $Env:ComputerName to $(hostname)

[mjr4077au]

@AlkHacNar, does [System.Environment]::MachineName work as you'd expect?

[AlkHacNar]

no, its the same as $Env:ComputerName

[mjr4077au]

Thanks mate, that's actually really good to know.

[AlkHacNar]

just tested (Get-WmiObject win32_computersystem).DNSHostName as @obuolinis mentioned and it works too in the sandbox