I just began trying to print again on my 4800, which has been idle since we moved a few months ago... Initially, for a few days, I was able to print, and the carts were being recognized. Then, after turning the machine off and the next day on, the Magenta and Light Magenta were both not being recognized. I was able to get the Magenta to be seen, but no matter what I do with the light M, I keep getting the "set cartridge" error. I was also getting "incompatible cartridge" error, but I managed to get that one to go away. Here is what I've tried: Resetting the chip many times. Pushing in a little harder, pushing to the right, and left, many times each. Using a piece of cardboard on the side of the cart to make sure the cart was engaging the chip reader well. I even removed the chip, added a thickness of paper behind it, and that is when I solved the "incompatible cart" error, but still I'm getting the "set cartridge" error. I have two re-setters... one for my 9800, which works well, and the one that came with my carts for the 4800, which does not work (just a quick flash of red), so, I've been using the 9800 re-setter. Any thoughts? Thank you!