C＃：在Windows 10升级后无法识别Arduino

Question

请检查我正在使用的代码：

public static string AutoDetectArduinoPort()
    {
        ConnectionOptions options = PrepareOptions();
        ManagementScope scope = PrepareScope(Environment.MachineName, options, @"\root\CIMV2");

        // Prepare the query and searcher objects.
        ObjectQuery objectQuery = new ObjectQuery("SELECT * FROM Win32_PnPEntity WHERE ConfigManagerErrorCode = 0");
        ManagementObjectSearcher portSearcher = new ManagementObjectSearcher(scope, objectQuery);

        using (portSearcher)
        {
            string portName = "";
            foreach (ManagementObject currentObject in portSearcher.Get())
            {
                if (currentObject != null)
                {
                    object currentObjectCaption = currentObject["Caption"];
                    if (currentObjectCaption != null)
                    {
                        portName = currentObjectCaption.ToString();

                        if (portName.Contains("(COM"))
                        {
                            if (portName.Contains("Arduino")) // e.g. "Arduino Mega 2560 (COM3)"
                            {
                                portName = portName.Substring(portName.LastIndexOf("(COM")).Replace("(", string.Empty).Replace(")", string.Empty);
                                return portName;
                            }
                        }
                    }
                }
            }
        }
        return null;
    }

我称之为：

string portName = AutoDetectArduinoPort();
MessageBox.Show(portName); // shows "COM3"

if (portName != null)
    {
        serialPort.PortName = portName;
        serialPort.Open();
        ......

运行时异常（System.IO.IOException）抛出最后一行，说＆＃34;端口＆＃39; COM3＆＃39;不存在。＆＃34;它显示在设备管理器和所有。

我做错了什么？请帮我解决这个问题。具有讽刺意味的是，在Windows 10升级之前它运行良好:(