@Sivakumar TK,
It doesn't seem like the variables are the issue as much as the actual command reference. I assume 'UserList' is the name of the PowerShell script/cmdlet you're trying to run? When you run this from Control Room are you running it against a runtime resource on the same machine as you are debugging on?
From what I can see in a few Microsoft articles this error usually implies the associated PowerShell module isn't available for some reason. Is this a custom PowerShell script you wrote? Can you share your actual C# code?
Cheers,
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Eric Wilson
Director, Integrations and Enablement
Blue Prism Digital Exchange
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