Thanks for the tip Jan, but I am afraid nothing worked we tried allsorts, the compatible cartridge just seem to mess up the whole connection. We searched the internet and found that this is a common problem with HP printers, suppose it makes sure you buy their cartridges and not opt for the cheaper option. Anyway yesterday we went out and bought a Cannon MG 5550 as I just couldn't be without my printer any longer. Hope we have made the right choice as its a bit confusing too many to choose from.