I bought three HP compatible colour cartridges in April 2022. When I tried to use them in January 2023 the printer refused to print and rejected the cartridges as being a non-genuine HP product. I raised this with Internet Ink who said they disclaimed liability for cartridge incompatibility with printer firmware. In effect, the problem was mine: either I would have to find a way to reverse previous upgrades to my printer firmware or I would have to throw away my cartridges. Internet Ink provide software to downgrade firmware for PC users, but not those unfortunate customers who own Macs. Instead, Internet Ink referred me to a link to firmware downgrades made available by a user on Reddit. However, if I downloaded from that source I would have to override the built in Mac security software and take the risk of running software damaging my laptop or printer. I would also risk breaking my printer warranty. Internet Ink have recently added a clause in their terms and conditions whereby they disclaim liability for cartridge incompatibility with printer firmware, and they include a slip of paper in the delivery of their products advising customers to turn off automatic firmware upgrades. However, when I bought my cartridges the warnings were less prominent, and the clause in their terms and conditions was not present. Despite this they refused to refund me or supply a replacement. I accept that compatible cartridge suppliers cannot future proof their products when the likes of HP write firmware updates to prevent these cartridges from working. However, the unsuspecting customer needs to be advised of the problem at the time of purchase, and if the supplier refuses to take responsibility this must be made clear at the time of purchase. Neither occurred at the time of purchase. I received very poor customer service from Internet Ink over this purchase when I raised this as a complaint. There is at least one of Internet Ink’s competitors that has a non quibble policy of refunding customers whose cartridges do not work. It is definitely worth shopping around for suppliers who take their contractual responsibilities seriously and treat their customers with respect.