I’m trying to add an object of a class as a NoteProperty to another class inside a ForEach-Object -Parallel block in PowerShell 7. However, when I try to call a method on that added NoteProperty, I get an "Object reference not set to an instance of an object" error. Here’s a simplified version of my code:

class test {}

$test = [test]::New()

1..2 | ForEach-Object -Parallel { 
    class test2 {
        testmethod () {
            Write-Host "test method called"
        }
    }
    Add-Member -InputObject $using:test -MemberType NoteProperty -Name "property$_" -Value ([test2]::New())
}

$test.property1.testmethod() 

If I do a Get-Member on $test.property1 I get the method testmethod in the output.

I understand that the issue might be related to how objects and properties are scoped within the parallel block. How can I correctly add the NoteProperty and ensure that the method call works outside the parallel block?

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It works with simple ForEach-Object without -Parallel.