I have replaced ink cartridges in the HP 7520 Photosmart before and had no problem. It is real easy.
Now, I had to replace the black cartridge on the left side of the ink cartridges. The old one came out fine, but I cannot get the new cartridge to go in! I don't know what I am doing wrong. I pulled of the plastic wrap, and twisted off the orange lever.
I cannot get the back of the cartridge to slide in between the side of the carrier and the color cartridge next to it. It does not want to go in. I am not even getting it in far enough to start pushing the front down. I have tried removing the color cartridge, but it doesn't help. I have compared old and new cartridges side by side. They look the same. Except, the old says 564 - installation, and the new one is 564-XL. I do think it is the first change since we bought the printer.
Photosmart 7520 all-in-one uses five ink cartridges. Photo, Magenta, Cyan, Yellow and Black. The cartridge on the left side is a Photo Cartridge. This cartridge is not the same as Black cartridge.
Please make sure that you are trying to install Photo cartridge in the left hand side slot. The Photo Ink cartridge will have a 'Bow Tie' icon and Black cartridge will have a 'Pentagon' icon on it. See the document below to learn more on difference between Black and Photo cartridge:
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