A bad dot falls on a bar code and the dot cannot be shifted. A gray box is printed instead of the bar code. However, 2D bar codes still print on the 9825/9850 printers when bad dots are present within the bar code field.

The print head has failed and can no longer "dot shift" to print the barcode. The print head must be replaced to rectify this fault.
Please contact Solaris Software to organise a replacement print head.