If you plugged the cutter in and Windows 10 failed to find a driver automatically, you will need to manually assign one. This is the most common fix for the JK series.
Older JK Series cutters use a 9-pin serial port. Windows 10 does not natively support these ports on modern laptops (which lack serial ports). You will need a USB-to-Serial (RS-232) adapter.
If you are using FlexiSign 8.1, 10, 12, or 19+: