My printer is 23 months old and has been trouble free. Changed an ink cartridge as normal and black ink will not print. All colours are ok. Done all the recommended troubleshooting but they have no effect. I had exactly this problem with a B110a I got for my Dad 3 months ago. I spent a day doing all the suggested solutions but as he lives 200 miles from me it was quicker just to replace the printer.
I've read many pages with the same problem, but never read a solution. It seems that is is a software or firmware problem to me - but would welcome hearing if anyone has found a solution.