How to configure your Zebra GK420D printer for printing Royal Mail 2D Barcode labels.
Windows users
Select the 'Devices and Printers' option within the 'Control Panel' of the computer
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5. Next click on the Dithering tab and select none.
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6. Then click 'Apply' and 'OK' and you will be returned to the 'Advanced' screen where you originally selected 'Printing Defaults'
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Any other setting here reduces the accuracy of the 2D barcode to the point where the labels you produce may not scan through the Royal Mail network.
67. Now that the printer has been calibrated, you are good to go printing your Royal Mail 2D barcode label
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