If Zen Studio gives the error message "Device Disconnected" then you need to focus on the PROG (mini-USB) cable.

Device Disconnected in Zen Studio is a common error and not a difficult problem to solve. It simply means there is a poor connection to the Zen, or you changed a setting in the Device Panel which crashed the Zen due to XYZ reasons. Let's first focus on the PROG (mini-USB cable).

1. If Zen Studio says "Device Disconnected" in the status bar, close it and unplug all USB cables from the Zen, because you're going to give it a hard reset and erase all memory slots. Connect the Zen to your PC using the CONSOLE/PC (micro-USB) cable and hold down the P1 and PS2 buttons until the RGB LEDs flash RED, GREEN, BLUE. Wait a few seconds then disconnect the micro-USB cable from Zen and open Zen Studio again.
2. Connect the Zen to your PC with ONLY the PROG (mini-USB) cable to a USB3 port (make sure it's onboard not an extension or USB hub). Also make sure it is plugged in fully as it can be a tight fit. The status bar should now say "Device Connected Zen FW <version>" - your Zen is working again, and you can continue as you were.
3. If it says "Device Connected But Not Responding", click the "Reset Device" button (this is useful if you don't have immediate access to the reset button), or click "Find Device" as this can help search for the Zen in case your PC's USB device drivers are corrupted.
4. If it says, "Device Disconnected", program the latest firmware to your Zen using the same PC USB port. If it works you know the USB Port is good, so try a different mini-USB cable to that same USB port.