I purchased a Digital Research External USB 2.0 320 GB Hardrive and my computer simply isn't recognizing it. I have tried installing it several times - with the computer turned on and off. Tried through the Install Hardware Wizard, and all the troubleshooters. I have tried all the different USB ports on my computer to see if that would make a difference, but no luck. It is simply not being recognized. My ports are USB 1.1., but I believe they are backward compatible. My puter is Pentium IV. Any suggestions?