Also works for these printers: HP 3320, HP 3420, HP 3520, HP 7660, HP 7760, HP 7960, HP 5150, HP 5850, HP 1280, HP 130, HP 230, HP 145, HP 245, HP 7350, HP 7550, HP 6122, HP 6127, HP 3820 and HP 656.
Here is a temporary fix that will print anything ony your HP 7550 and other HP printers until hp does come out with a software update. The only thing that it doesn't do is tell you how much ink is remaining in each cartridge when it prints but you can always run a diagnostict test page to figure that out.
I know it works for the 7550 but haven't tried it for the other printers listed.
http://h10025.www1.hp.com/ewfrf/wc/document?docname=c00808478&lc=en&cc=us&dlc=e&product=87608
