I'm using a USB to Serial Converter (Moxa brand) box. A few times a week this box locks up. To reset the box, I can reboot the computer, or unplug the box, or Disable/Enable USB device in device manager. I'm probably eventually going to replace the converter box with a conventional RS232 Serial board. In the meantime, I think there must be a way to programmitically Disable and then Enable this USB device.