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I gave them 1 star because there was no opportunity to give them 0. I installed the Black ink cartridge and it lasted less than a day. After that no ink came out at all, the pages were blank. I reinstalled the older HP cartridge and the printer worked fine. But it was almost out of ink. So I tried again to reinstall the Coloworld cartridge and once again I realigned it. This time it did not work at all. I had ordered two sets of cartridges, so I installed the second Black cartridge. I got the same result. They did not work. I will be returning both sets for full refund.
I put the new cartridge in my printer today and printed out 14 slides of minimal printing in greyscale on each and then it ran out. I didn't get a chance to use the colour as it won't let me use it at all as the black cartridge is showing as completely empty so I can't comment on that one.