I guess that I am one of the many who fell into the trap when formatting my drive to Mac OS Extended and now having a corrupted drive (mine is a BuffaloMiniStationLite HD-PEU2 500G)...
The worse is that, I cannot delete the partition, nor as simple as unmounting the drive from my Mac. Not to mention that basically the drive is not usable right now. No matter what I did with the Disk Utility (erase, re-partition, or even just eject), it just failed with a message saying "The disk "BUFFALO HD-PEU2 Media" could not be unmounted".
What I have done when the drive is out of the box...
1. Connected to my MBP
2. Successfully mount and access the drive, then found TurboUSB, installed, then rebooted.
3. Then read the instruction that I shall probably better reformat the drive with Mac OS Extended.
4. Open the Disk Utility, and chose "Erase" with Mac OS Extended, with a new Volume name.
5. Since then, everything failed.
Need help please...
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My stuff: Buffalo MiniStationLite HD-PEU2 500G, Mac MBP 2.4GHz, OS X 10.5.8