It's printing upside down!
Several times (now in history) I've had to deal with people complaining that the printer was printing the letters upside down, to go to the print room, pause the print run because clearly leaving it to carry on printing 100 letters in the meantime was the best plan, open the paper drawer and rotate the sheaf of headed paper by 180 degrees so the heading was in the correct location - as stated by the large label I'd previously affixed to the front of the paper drawer ("Headed paper only, heading this end, face down"). Also removing the plain paper from the headed drawer, readjusting the paper-size margins and the old classic of pressing 'resume' on the printer to compel it to print the 'letter' format document onto the A4 sized paper when it has "stopped working again". Amazing the number of times one could resolve a problem by simply reading the information displayed on the LCD screen and doing what it said.