So I've gone to the store and bought two different types of external hard drives for my Dell Dimension 2400. Both were recognized that they were there by the computer but it was asking me to install something. The two hard drives were 320 GB, 2.0 USB "Plug and Play" so there was no install. I'm wondering if its a problem with the Dimension 2400 or maybe just a software problem? Any suggestions would be appreciated. Also I've contacted the maker of the product and went through their steps to fixing the problem and twice now they have told me that the product might be defective, I've returned both of them twice now so that seems not to be the case.