Hi there.

I do have close to the same issue. When I fist run my application it connect successfully to serial port. Now my app can receive and send data. But when I close my app I has some issues running again. It looks like it goes into a tight loop. I'm running this app on a mobile 5.0.

Andreas

On your Mobile 5.0 computer, after exiting the application check the computer's memory to see that it really exited and not just hidden. Also, make sure the program closes the port before exiting.

What is it trying to do in that tight loop ? Trying to open the port, but the CreateFile() failes?