I am having trouble getting a scanner to work with windows 7. The computer recognises the printer but not the scanner. I have tried 3 different multi-function printers with the same result. Using a HP Photosmart C4480 an error message 8,[(02-21474672590] comes up. I thought i might need to re-install windows 7 as re-installing the printer drivers does not solve the problem - or could it be a hardware problem, although I have tried plugging in to 2 different USB ports on the computer. Can anyone give me some guidance? With thanks.