Printer is a Samsung ML-2240, quite old. I have for the past 5 years bought compatible cartridges and refilled when required. Only changed carts when the printing got iffy.From memory I have never had one stop printing until today. It was getting low on toner so topped it up reinserted cart and it wouldnt print. I can press the button on it and it will print out the printer specs so the printer itself appears ok. So, is it likely to be the page count (cartridge chip) that is preventing it working? And if I get another cartridge is that likely to cure it by having a new chip in the cartridge.