BlackLightComet:
On the Opening and closing the serial port, well, as I said, that was literally the only way I could get to work without opening the Arduino SM first. Though I would be fully willing to accept it could be the issue, if someone with higher knowledge wants to tell to tell me so.
I did not say that your program is opening and closing the serial port - I don't know. You need to figure out if it is. I just explained how there would be a problem if it is happening.
Have you looked at my Python code? It should work with Windows if you change the references to the Serial port to the Windows' style.
A common reason why something won't work without opening the Serial Monitor first is the failure to set the DTR and RTS settings for the serial port.
...R