Ive noticed that alot of people are having trouble with updating te firmware with the comport and i had the same trouble my self. I was from a cable i made myself and with a bit of messing around with it i have managed to get it working. One of the problems that i have noticed is that the cable that is showing on the web was as if you are comming directly of the com prot connection from the back of the computer but infact most people will use a com port cable and might have a null modem cable which changes from one end to the other. If you come across this problem make sure that you have the right cable pinouts from the box to the com pinouts or you will keep getting the error it has to be right