I just replaced my black ink HP 74 cartridge as I have done many times and suddenly am getting a message that this cartridge is not compatible. When I put the old cartridge back in, everything works and I get a "low ink--replace soon" message. What's going on? This HP 74 cartridge is new and the same type I always buy.

My printer is an HP Photosmart All-in-One C4480.

Sounds like a defective cartridge. Return it to the store. Are you sure its not a refilled cart?

I do believe you are right about the defective cartridge. I happened to have another new cartridge on hand, inserted it, and the printer is working perfectly.

I have learned to keep my receipts so will head to the store today. No, it is not a refilled cartridge, but, supposedly, a brand new HP 74 cartridge.

Thanks.