k thanks ! I got a email back from MPPSolar and they said if I'm not getting a code , it may not need a Firmware update ! I sent them a video of what Inverter is doing but have not heard back yet on that !You need a USB to serial convertor, if your PC does not have a serial port. The software to update the firmware uses a serial port (COM 1, COM 2, etc.) to communicate with the inverter. There are two devices in the inverter with firmware that can be updated.