I have the same problem. As soon as I installed 4.2, my laptop does not detect my recorder. It does recognize a usb connected but it can't seem to get the correct driver for it. I wonder if it is a software bug or a windows problem??? I have a MZ-N910. It's really frustrating as I have tried to install and re-install numerous times in 3 different laptops and they all show the same freakin problem!!!!!! HELP!!!