9 Replies Latest reply: Feb 8, 2012 9:05 PM by olivejuice09
olivejuice09 Level 1 (0 points)

I have a Buffalo external hard drive (HD-CX500U2) that is (according to the manual) "locked." I let my father-in-law borrow it (he has a pc ugh!).  He gave it back and now my Mac doesnt detect it!! I get a prompt telling me "The disk you inserted was not readable by this computer" and it has 3 buttons "initialize" "ignore" and "eject." When I click on "Initialize" it takes me to Disk Utility and I can see the external HD there! I want to know if any of you can help me unlock it through my Mac? We tried to unlock it from his pc but it didn't work :/ Please help!


I have a Macbook Pro with Mac OS X v10.6.8

MacBook Pro, Mac OS X (10.6.8)
  • noondaywitch Level 6 (8,135 points)

    Sounds like the formatting has been corrupted.

    You'll need to use Disk Utility to repartition and format the drive.


    What format was it before it was borrowed?

    The Mac uses HFS+ with a GUID partition scheme.


    PC uses NTFS with a MBR partition.


    NTFS is read only on Mac, HFS+ will not be recognised by Windows (at least without additional software).


    If you intend using it for both you should use FAT32 (listed as MSDOS in Disk Utility) with MBR partition.

  • olivejuice09 Level 1 (0 points)

    :/ I actually don't know what format it was in I'm guessing HFS+ because he said he was not able to open or even see my hard drive on his computer.


    How do I repartition it?

  • OGELTHORPE Level 8 (42,800 points)

    Format and partition are not the same though both are performed in DISK UTILITY.


    To format, go to the erase panel and select the HDD listed in the column on the right so it appears in the "Name' Field.  Select the desired format from the 'Format' menu per noondaywitsh's suggestion MS-DOS (FAT) if you want it compatible with you computer and a PC.  If you want to use it just for your computer, Mac OS Extended (Journaled) is appropriate.


    To partition the HDD, select again from the right hand column the external drive (it will be the top name showing 'Ext Hard Disk ....") and select the 'Partition' panel.  Follow the instructions shown.



  • noondaywitch Level 6 (8,135 points)

    First of all, is (was) there anything on there that you desperately need to retrieve?

    If so you'd best have a look with recovery software such as Data Rescue 3 to see if it's salvageable. (The checking software is a free download, but you have to buy the full App to actually rescue anything).


    If there's nothing there to justify that expense, open Disk Utility again and select the external drive in the left hand pane - the actual drive with the maker's name and size.


    Run Repair Disk. (Not permissions).

    If that comes up as disk OK, click the partition tab. Select the partiton from the drop-down above the graphic; 1 partiton is all you need.

    **Go to the options button and ensure that the partition scheme is GUID and the file system to Mac OS Extended (Journalled). {This is the same as HFS+}.**

    Name the partiton (whatever it was called before is fine), click Apply.

    When the new volume appears in the sidebar (indented to the right below the drive) you're ready to start using the Drive.


    **If you want to be able to use it on your dad's PC too,

    Select Master Boot Record (MBR) at the partition stage, and set the file system FAT32 (MSDoS)**


    If you get errors when repairing the disc prior to partitioning, run the repair disc again until the only message you get is the "The Volume XYZ appears To Be OK".


    If a message appears that the disc can't be repaired, continue with the partitioning, but if the partition and format is successful, run the Repair Disc again to ensure the problems have been solved.


    Note - Repair Disc won't work on a FAT32 drive.

  • olivejuice09 Level 1 (0 points)

    Will this erase any files in the hard drive? Because of course (like everyone else) I have many important files I cannot lose.

  • olivejuice09 Level 1 (0 points)

    I actually cannot select repair disk because it is grayed out. Do you recomend I go through with the steps you recomended?

  • noondaywitch Level 6 (8,135 points)

    That suggests that there's no readable partition on there.


    Go ahead with the partitioning from the ** section, skipping the repair.

    You've nothing to lose at this point, and it should (crosses fingers) recover the drive.

  • olivejuice09 Level 1 (0 points)

    Thank you! You have bee super helpfull!

  • olivejuice09 Level 1 (0 points)

    And by the way you are right there is nothing on the drive anymore :'( I went to a "geek squad" and they confirmed that there is absolutely nothing on there anymore! :'(..My next step will be to try my best and try to recover it.  They told me that they could do it for me but they were going to charge me an arm and a leg >:0/ So I'll see what I can do without losing my arm and my leg lol!