I have an HP Photosmart 7525 printer. It was working fine and then it stopped printing black. All the ink cartridges are new. The ink level tool shows them all being full. It would print color but not black. I followed the instructions online all the way to the point to cleaning the print head. Now it does not print anything! It says there is a problem with the ink or the printer. According to the manual I should replace the print head but it's 75.00. Not sure if it's worth it. Thoughts??