Print cartridge doesnt work

Did you replace it with an official HP cartridge? If not, you will see that message, the printer won't see it properly. It may still print unless the ink got so low that it did not print at all before the replacement. If it's an official HP cartridge, get a new one and try that. Should be easy to bring back to the store.

Yes, I used an HP cartridge. Tried another cartridge, same thing. looked on the internet and it seems a lot of people are having this problem and HP is taking back the ones that are under warranty. Unfortunately, mine isn't. Other ideas are welcome! Thanks for your suggestion.

Try cleaning the contacts. You can try to replace the mechanism but inkjets are made pretty cheaply, they are almost disposable.

It happens when you use a refilled cartridge. While using a refiled cartridge the printer doesn't know the actual level of the ink in the cartridge. If you replace it with the original HP cartridge, the error message will go. Refilled ink cartridges are usually cheaper than the original ones. don't worry about the message if you bought a refilled cartridge, they usually work fine.