Here is the error message code that I got which I don't know.
Connecting to remote server failed with the following error message : The WS-Management service does not support the request. For more information, see the about_Remote_Troubleshooting Help topic.
ErrorCode -2144108428 int
I would start by just trying to use this in Powershell first to make sure you're using the correct URL settings and you don't have any issues with firewall,preReqs or authentication. Once you know the setting that work transfer that into you .NET code.
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