Check the internal printer to see if the ON LINE light is illuminated.  If not, press the On Line button.  Check to make certain the printer door is latched properly.  Check to see if there is paper in the printer. If the printer is putting out blank paper, then it is likely that the thermal paper roll is installed backwards.  Check to make sure the paper roll is inserted so that the paper comes out over the top of the roll, not from underneath the roll. If using an external printer, check the cable connection on the rear of the Intox EC/IR and make sure it is attached on both ends.  Check to make sure there is paper in the printer and it is turned on and ready to print.