I had the "Printer or Ink System Error" on my HP 7612 large format printer. I tried every thing listed on the troubleshooting guides and support forums with no success. Then I CAREFULLY emptied out the ink waste and the problem went away. Be very careful picking up or moving your printer (even to transport it for servicing). If the ink waste tray is full the ink will run all over the inside of the printer and leak out wherever it can. It was messy, but now my printer is working again! Everytime the the printer cleans the heads/nozzles it pumps ink into the waste tray. I went out and bought an inexpensive B&W laser printer to use for basic printing in hopes of putting off this cleaning exercise for as long as possible. I have to say I have had nothing but bad experiences with HP printers and will not buy one again. My 10 year old Brother MFC still works perfectly!