WD External Hard drive not recognized in my computer

Hi, I had same problem with my 320GB and I went to ADD HARDWARE in the CONTROL PANEL and ran a scan, it didn’t find it, but I said yes to IS HARDWARD CONNECTED, then clicked next… next again, then it could see it but it had DISABLED it… agreed to ENABLE device and my computer can see it now… so goto your control panel in MY COMPUTER and see if it sees it…