Funny you should ask about software installation. Yes, I have installed it multiple times and the scan function refuses to work with my HP desktop computer (it performs the scan and crashes trying to save it to the PC). The scan function works perfectly with all other (non-HP) PCs I have connected to it through my home wireless network. All inquiries to HP support end with the response that the C7280 is out of warranty and they are not interested in problems I have with it not working with my in warranty HP computer.
As far as the humidity in the room, it is an air conditioned room maintained at 50-60% RH. And I don't have the problem with my Canon printer located on the other side of my computer.