Windows can not find my COM port after it briefly disappeared about pyserial HOT 2 OPEN

When the device disappears and reapers while the port is open, it won't work under the old name. Other operating systems tend to assign a new device in such cases, e.g. under Linux, it may become /dv/ttyUSB1 and /dev/ttyUSB0 will disappear as soon as the application closes the port. Windows tries to assign the same COM port for the device so the old instance shadows the new one, or something like that.

I know of no workaround. Maybe there are solutions, e.g. if the device is connected through a hub, the hub could be disabled or the device itself could be powered down. USB has such commands but i do not know of a Windows API that exposes these (never looked for that).
Alternatively, make your device slower so that the PC can close the port before the device reappears on USB... like an additional delay at startup (maybe only when the device is in test mode).

A silly alternative would be to use two (or more?) alternating serial numbers for the device, so it would get a different COM port after each reboot of the device. But i would not suggest to really do this.

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Hope it helps someone to come up with a solution: this problem has a workaround for C# http://stackoverflow.com/a/9057158/396583 And it works reliably. Port gets reopened alright after replugging USB cable.

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