@Butters,thank you for your reply! The thing is that although I've tried so many times to proceed as above mentioned, the device still doesn't respond on any of the CURE firmware RGN. If I flash "QuickCure" or any other CURE.rgn made from previous SW than 590, the device is always disconnected 1-2 seconds after I hit the Enter key. The only RGN which keeps the device locked in preboot until the flash finishes is the one made from sw 590 but even so the device starts without Mass Storage Mode.Regardless the USB port used for this procedure, desktop PC or laptop, the result is the same.