Sorry,I know there are lots of these threads but none of them solved my issue. I have a WesternDigital (WD) 640 GB External hard drive. Had it for about 2 years now and a few days ago it stopped working; First, It doesent show up in my computer also it wont show up in the Disk Management but the USB works because when i plug it in it recognizes it. BTW i am using a Windows Vista and my hard drive number is WDBAAA6400ABK-00 That is what it says on the case. HELP PLEASE!!!
Can you feel the disk spin up when you apply power?
If it spins up and the drive isn't showing in disk management, then the first thing to do is remove the disk from the USB enclosure and connect it directly to a SATA port on a desktop and see if it is identified correctly by model number in the BIOS.