I have a model WD500HiU-00 and my PC (Vista OS) no longer recognizes the drive. I have run through the trouble shooting suggestion to no avail. I have run the extended diagnostics (2hr+) and the results show no disc problems. I have replaced the USB cable, plugged the power supply into the wall directly, used different USB ports, and plugged into the USB
port directly on the computer. The drive seems to spin up because I can feel it vibrate and the blue light is on. I know that this is an older unit and my computer hard drive is still OK, so I could just buy a new external back-up drive and start the back up process again, and I am retired and money is tight. Any help would be greatly appreciated.