serproxy alternative or auto-config?

I'm using a mega 2560 in a kiosk, the 2560 is in a control box that's unplugged from time to time and even using the same USB port changes the com port. Trying to explain how to look up what com-port its on to a non-tech is proving challenging. Is there anyway to auto set the config or launch serproxy when a device is plugged in? google did not turn out any alternatives. Anyone know of a better solution, maybe a way to force a com-port?

What OS?

win 7 (x64)