Why isn't my printer printing?

I have hooked my printer up to my wireless router via ethernet cable. Have installed all the drivers n programs needed and all diagnostic checks say that it is ready to print. But when I go to print it says that theres an error printing. Any ideas why...

i dont get it its printing words but not pics.. what could it be??

Its a hp photosmart c4500 series. it only prints when it wants. it makes copies and everything. its online, it just says printer failed to print... help!

my kodak 5100 printer wont print, the file is going through the paper is getting brought into the printer and it makes the noises and gesters as if it was printing but the paper comes out blank what should i do i even replaced the ink

I have put an ink cartridge in but the printer behaves as if it is printing but it is clear the ink is not getting through i am lost help

im using both an hp printer and an hp laptop, it worked fine last week but now its not printing.

on my kodak ESP 5 Aio and HP psc 1310 series isnt printing the background color and i need it to so the letters will show up. i cant change the color of the background to work because it look right i need help. im getting FRUSTRATED.

Wheneevr i try to print something it says its printing but nothing happens why is this?

i have Canon MP150, and it has always worked, but now it is not printing anything, I have cleaned all nozzles, deep cleaning etc, and still nothing. Yes, there is ink in cartridges....Anyone got any ideas please.