When adding new paper to your barcode label printer or changing to a different size label, you may notice that the labels come out off-center, or two labels are used to print one barcode.
In this case, the barcode printer needs to be calibrated. This is very easy to fix.
For the Zebra LP 2824 and GX420d
Press and hold the button on top of the printer. Watch the green LED light, which will flash once, then pause, then flash twice. Release the button as soon as you see it flash twice. The printer will now calibrate for the correct label size and should function properly again.
For the Zebra ZD410
Hold down the Pause button and X button the on top of the printer for 2 seconds, then release. The printer will now calibrate for the correct label size and should function properly again.