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        private static void InstallProductKey(string productKey)
        {
            ManagementClass managementClass = new ManagementClass("SoftwareLicensingService");

            /* foreach (MethodData methodData in managementClass.Methods)
            {
                Debug.WriteLine(methodData.Name);
                if (methodData.InParameters != null && methodData.InParameters.Properties.Count > 0)
                {
                    foreach (PropertyData propertyData in methodData.InParameters.Properties)
                    {
                        Debug.WriteLine($"    {propertyData.Type} {propertyData.Name}");
                    }
                }
            } */

            // InstallProductKey method of the SoftwareLicensingService class
            // https://learn.microsoft.com/en-us/previous-versions/windows/desktop/sppwmi/installproductkey-softwarelicensingservice
            // unit32 InstallProductKey([in] string ProductKey);
            ManagementBaseObject inParams = managementClass.GetMethodParameters("InstallProductKey");
            inParams["ProductKey"] = productKey;

            //object[] methodArguments = { productKey };

            try
            {
                // object result = managementClass.InvokeMethod("InstallProductKey", methodArguments);
                var result = managementClass.InvokeMethod("InstallProductKey", inParams, null);

                Console.WriteLine($"Installing product key returned: {result}");
            }
            catch (Exception e)
            {

                Console.WriteLine("Failed to execute method");
                Console.WriteLine(e.Message);
                throw;
            }
        }					

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var result = managementClass.InvokeMethod("InstallProductKey", object[] { productKey });