ManagmentClass实例化时报错

        调用system.management时，下文代码中第三行运行会报错，报错内容为：

System.Runtime.InteropServices.MarshalDirectiveException:“Cannot marshal 'parameter #3': Cannot marshal a string by-value with the [Out] attribute.”

原代码：
            ManagementBaseObject inPar = null;
            ManagementBaseObject outPar = null;
           //下面这一行代码报错
            ManagementClass mc = new ManagementClass("Win32_NetworkAdapterConf**iguration");
            ManagementObjectCollection moc = mc.GetInstances();
            foreach (ManagementObject mo in moc)
            {
                if (!(bool)mo["IPEnabled"])
                    continue;
                string[] addresses = (string[])mo["IPAddress"];
                if (addresses[0].Contains("xxx.xxx.xxx.xxx"))
                {
                    Console.WriteLine("不修改保护的地址");
                    continue;
                }
                Console.WriteLine("开始修改");
                try
                {
                    //设置ip地址和子网掩码 
                    inPar = mo.GetMethodParameters("EnableStatic");
                    inPar["IPAddress"] = new string[] { ip };
                    inPar["SubnetMask"] = new string[] { mask };//"255.255.255.0"
                    outPar = mo.InvokeMethod("EnableStatic", inPar, null);
                    //设置网关地址 
                    inPar = mo.GetMethodParameters("SetGateways");
                    inPar["DefaultIPGateway"] = new string[] { host };
                    outPar = mo.InvokeMethod("SetGateways", inPar, null);
                }
                catch (Exception e)
                {
                    Console.WriteLine(e.Message);
                }