0 Replies Latest reply: Aug 2, 2008 6:53 PM by Courcoul
Courcoul Level 6 Level 6 (12,220 points)
Hard disk drives used in Windows XP or Vista are partitioned using a Master Boot Record scheme and formatted in NTFS format by default. MacOS X can read these drives but cannot write to them without extra third-party software. Needless to say, you cannot install MacOS X nor can you boot from these drives.

What happens if you want to reuse such a drive, or if you purchase an external drive which comes preformatted for these systems? You need to change the partitioning scheme from MBR to GUID and the format from NTFS to MacOS Extended (Journaled) if you want MacOS X to boot from that drive, but there's a bug in Leopard's Disk Utility that impedes erasing an NTFS HD directly, so you have to use the following workaround:
# Make the drive available to the MacOS system (plug it in, power it up, etc. Firewire and USB drives are plug and play, SATA, e-SATA or PATA drives are not and need to be connected with the system powered down).
# The NTFS volume should appear on the Mac desktop, unless password-protected. Remember that all data in the volume is going to be lost with this procedure.
# Open Disk Utility and select the device containing the NTFS volume. The Partition tab should appear, in between Erase and RAID. Click on Partition.
# The Volume Scheme and Information will be displayed, but DU will say that "The NTFS volume will not be erased" and all buttons will be grayed out. This is the bug and here comes the workaround.
# Click on the "Current" drop down menu and select "2 partitions" or more. The Options button will activate.
# Click on the Options button. Select *+GUID Partition Table+* if you are using an Intel Mac, select *+Apple Partition Map+* if you are using a PPC Mac. Click OK.
# You can now go back to "1 Partition" or as many as you want for the drive. Click Apply and let DU create and format the partition(s). Time Machine may pop up a window asking to use the volume(s) for backups; click Cancel.
# Select the new volume(s) on the left column and verify that the format is +Mac Os Extended (Journaled)+. If not, click on the Erase tab and correct.
# You have successfuly eliminated the NTFS formatting from the HD and it can now be used to install or clone a bootable MacOS X 10.5 startup volume. Quit Disk Utility.

PowerBook G4 15/1.25GHz, MacBook Pro 15/2.5GHz, Mac OS X (10.5.4)