You need a TWAIN driver. Based on the questions related to HP AiO devices I've seen, HP does not seem to ship a TWAIN driver with the device, and you need to download it from their web site. However, if you want to use this device with a Mac, you seem to be out of luck (again, this is based on on first hand experience, but on what I've gathered from other users - I don't use any HP device).
Karl Heinz Kremer
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