title: How to Forcefully close SerialPort Connection?
body: <p>I have device which is connect to PC via USB Serial communication. I am performing following steps</p>
  <ol>
  <li>Start Device (Power On)</li>
  <li>Device will detected in my PC as COMx name</li>
  <li>Start my application</li>
  <li>On base of COM PID/VID, I connect to device</li>
  <li>Perform communication. (Up to this I am not facing any problem)</li>
  <li>when I switch off device, device is disconnected but I cannot able close connection.</li>
  <li>When I again start(Switch on) device, Device is detected but my application cannot able to connect to COMx(device). It throws IOException &quot;COMx does not exist&quot;</li>
  </ol>
  <p>So I think I have some way to close communication port forcefully.</p>