Hi all,
I had exactly the problem with WD passport 300GB after I'd changed from FAT32 to NTSF.
No solutions provided here solved my problem.
But my WD is back and running great and here is how.
go to control panel - adm. tools - services
Scroll down to find WD Drive Manager Service
Look at 'Startup Type' in the middle to see if its "Disabled"
If it is, turn it back to "Automatic"
Then the buttons under 'Service status' will be activated.
Press 'Start'
And then 'Apply'.
Disconnect your ext. HD from USB port and reconnect.
Magically there I saw the lights back on and device recognized.
I hope this will help for those who r biting nails with fear of losing precious data.
