Ben;
thanks for your reply. Yes, listing the ports works fine. That's waht the getPorts() method in the first line of code does. It returns COM1 and COM2 as serial ports.
I was thinking about other processes not letting go of the port too, to test it I did two things: 1) insert the code to check for port in use, and 2) rebooted and tried it first thing.
I'm really not sure how to proceed on this. Perhaps I should take this code out into an independent class and run it on another machine. Can't think of many more approaches...
ms