Disk Utility: Unable to format disk 500 GB or larger

When attempting to format a disk that is 500 GB or larger, Disk Utility in Mac OS X 10.5 may not successfully format the disk, and this alert may appear:

"File system formatter failed".

This article has been archived and is no longer updated by Apple.

Format the disk in the following manner (as described in this article). Note: Simply erasing the drive without partitioning will not resolve the issue.

  1. Back up your important data. Important: Partitioning a hard disk erases all data on the disk.
  2. Open Disk Utility:
    • If you're started from a Mac OS X installation disc, choose Disk Utility from the Utilities menu.
    • If you're started from your computer's Mac OS X volume, open Disk Utility from the Utilities folder. You can get there by choosing Utilities from the Finder's Go menu.
  3. Select the disk you want to erase.
  4. Click the Partition tab in the Disk Utility window. If the partition tab is not visible, make sure you've selected the disk (not volume) in the left side of the window.

    Tip: In Disk Utility, volume names are indented on the left side of the window. Disk names are not indented.
  5. Choose the desired number of partitions from the Volume Scheme pop-up menu. It's OK to choose "1 Partition" if you only want one.
  6. Click Options.

    Note: On some Intel-based Macs, the Options button does not appear under the partition tab. Use the erase tab to erase the disk instead. This will change the partition scheme to the default "GUID Partition Scheme". You can then use the partition tab to create additional partitions if desired.
  7. From the Partition Scheme pop-up menu, choose "GUID Partition Scheme".
  8. Click OK.
  9. Make any other changes you wish in the Volume Information section, such as partition size(s) or naming.
  10. Click the Partition button to erase your disk and install the new partition scheme.
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