I'm having trouble booting my PowerMac G4 from an external USB drive. Can you help?

I'm having trouble booting my PowerMac G4 from an external USB drive. Can you help?

Remember to select the disk, not a volume.


The answer theoretically depends on which model G4 you have. According to Apple, USB-booting support was added to Macs as of the AGP Graphics G4 and Slot-Loading (gumdrop) iMac G3, both circa late 1999. In reality, assuming your Mac is up to snuff, the problem probably lies with your USB drive. Such devices often come preformatted for optimal performance on Windows, which the Mac will happily support - until you try booting off the drive.


Launch Disk Utility (/Applications/Utilities), select the problematic disk from the list on the left (select the disk, not the subset volume), and click the Partition tab. The Volume Format pull-down menu should display some variation of Mac OS Extended. If it shows an MS-DOS or Unix file system, you’ll have to reformat, so take a minute to back up anything on the drive if you need to. Change the pull-down menu’s value to some flavor of Mac OS Extended, then click Options, and select Apple Partition Map. Click OK, uncheck the box labeled Install Mac OS 9 Drivers, and click Partition. Then clone your system to the newly formatted drive - we recommend using a utility called SuperDuper; the free version can clone your boot drive (an enhanced version is $27.95, www.shirt-pocket.com). Now try booting from the external drive.


Oh, and if your USB drive is already in Mac OS Extended format, check the partition map and reformat without installing OS 9 drivers - it sounds like voodoo, but we hear that it’s worked.




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