I had a problem with my HP Officejet 6210. I called it in since I had a warranty. I bought it in June 2006 and started having printing problems in 12/06. They sent me a remanufactured one to replace the almost new one. I called in again and spoke with a salesperson  because my computer would not read that there was a scanner also attached to the product. I got that resolved while on the phone and then the salesperson starts giving me a sales pitch. He said I could buy printer cartridge 96/97 combo for my Officejet which I would be saving money because they hold more ink than the 94 or 95. I was shopping at Costco and decided to purchase the 96/97 combo from them. I get it home only to find that I can't use the 96 black ink cartridge on my Officejet.  I contact the HP people because they advised me to purchase this product. They kept telling me to return the item to Costco because I bought it there.  I was not sure if Costco would take it back because it was opened and the label removed from the opening where the ink comes out. I made several attempts with multiple people to get an acknowledgement that it was their fault that I bought this item and they should be responsible for making me a happy camper. To this day nothing, however Costco did take back the product. Question-why sell the two cartridges together if you can only use one of them? Am I supposed to throw the other one away!