Hello, I am a single mom who needs to watch my spending and could use some help with an error message I keep receiving on my HP PSC 950 All-In-One Printer. I went down to Costco to buy a new black cartridge when they told me that they could refill my old one for $10, which could help me save some money, so I said yes. When I returned home and installed the black cartridge, the printer gave me an error message to "check the black cartridge." I checked it and it still didn't work, so I went back to Costco and bought a brand new HP black cartridge and installed it, and I'm still getting the same message. I decided to look on the HP website and cleaned the cartridges and reinstalled them, and that didn't work. Can anyone help me? I don't want to have to buy a new printer.