GK420D og LP2844-Z:

1. Press and hold the feed button while the printer is on.
   
   
2. During this it will flash in sequences 1, 1-2, 1-2-3, 1-2-3-4.
   
   
3. Allow it to flash twice and release the button.
   
   
4. 3-5 blank labels will come out.
   
   
5. Press the feed button one time to exit dump mode. A label with the message "Out of dump" will be printed.
   
   
6. The calibration has been performed.

ZD421, ZD420, ZD411 and ZD410:

1. Close the printer so the media is locked in and ensure the printer is powered and turned on.
   
   
2. Press and hold the outer two buttons on the printer (the Pause and Cancel buttons).
   
   
3. Hold down the buttons for approximately 3 seconds until the printer starts feeding out blank labels. Blank labels will continue to feed out until the sensor is calibrated. 
   
   
4. The labels should now be in the correct starting position and ready to print. 
   
   
5. The status light will go back to solid green and the calibration has been performed.