The black cartridge 17 was used up so black printing was fuzzy. I installed a new cartridge in the manner I had done previously. But it did not work this time. There was no black on the test pages and a text print gave nothing. Color continues to be ok. I then tried another new cartridge with the same negative result. I put the old cartridge back and that worked.
I have carried out tests suggested by Lexmark Help but they have not helped to find out what the problem is.
