WD is showing up on the system but is unaccessible

Hi,

I have WD passport 1TB external hard disk. When connected to my computer, it is being detected, but at the same time nothing shows up when trying to browse it. Any suggestion will deeply appreciated, as I dont wanna loose the data on it.

I have the same issue on my new asus  ma597 mb using windows 8.1.  If I move it from the usb 3.0 port to the usb2.0 port it works.  My other laptop running win8.1 does not have the same issue witht eh drive on usb 3.0  I have tried all the differet bios settings on the MB without luck.  Everyting on the pc is up to date.  I tried to do the firmware update on the drive but the firmware update will not run from either a win 7 pc or win 8 pc.  No sure what to do next.