: DiskWarrior Issue

Mar 3rd, 2008, 11:22 AM
I recently updated to DiskWarrior 4.1 and installed it on my external drive that is partitioned to have Time Machine and a bootable copy of my hard drive. In the past I used to run DiskWarrior from the external because booting up on the DVD is very slow. With this DW and OS 10.5.2 I now get an error message when I go to run DW from the external.
I checked DW support and they say"For Intel-based Macintosh computers, the drive must be partitioned as GUID Partition Table" (also known as GPT)."
As luck would have it, I partitioned my external Apple Partition Map :(
I don't know what the difference is. Is one better than the other? Is it worth reformatting and repartitioning to GPT so I can run DW?
I have an Intel iMac and would appreciate any advice/explanation.

Mar 3rd, 2008, 02:14 PM
Reformat the HD if you can, note that this erases everything on the HD. The new Intel Machines require this format for booting.

See Universal Binary Programming Guidelines, Second Edition: Disk Partitions (http://developer.apple.com/documentation/MacOSX/Conceptual/universal_binary/universal_binary_tips/chapter_5_section_10.html)

More info is here, if you want to go beyond the basics
Technical Note TN2166: Secrets of the GPT (http://developer.apple.com/technotes/tn2006/tn2166.html)

Mar 3rd, 2008, 04:08 PM
Thanks Kosh. The odd thing is that I have had this external drive partitioned this way since Nov with Time Machine and a bootable copy (which has worked fine). I have researched and found that in a lot of cases, neither should have worked.
I am going to reformat and do it right this time; don't want take any chances with Time Machine if I ever travel back in time. :)