It would seem, at least to the system, that there is a problem with the version of OS X that is on that external.
If the drive does not show on an Option Start, then the firmware does not recognize the OS that is on the external as "valid"
Your best bet, to begin with, is to reinstall the OS onto the external using the Archive and Install option. This just replaces the system but leaves everything else intact.
Do that, reboot and let us know the outcome
P
I have a whole console log full of these messages and no clue as to what to do about it. Apple's support website doesn't have anything about this, neither does anybody else it seems. Can somebody help, please?
Macmini PPC running OS X 10.4.11
(The original problem was/is not being able to boot from a firewire drive which both shows as bootable and verifies fine in Disk Utility. The drive doesn't show on option-start on either the ppc or my (intel) MacBook. Btw, the MacBook console log does not have any "error loading prefs - creating defaults one" messages.
If you can offer help on the external drive problem as well, without my having to erase the drive, I'd appreciate that too. The mini *has* booted off that drive in the past...)

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