Bad!
You may have a corrupt OS on the external Firewire drive. What OS is it?
It might be fixed with the judicious application of Disk Warrior, an Archive and Install or a belting with a 4 pound hammer.
How does starting from the FW drive help when you are working with music? Is it the larger storage capacity?
Does the drive actually rotate, can you hear it running? Does it mount on the desktop when you start from the internal HD?
Have you done anything to the system recently? Was the drive connected during one of the Software updates? You do software updates?
What a lot of questions: Answers would help us help
P
I have OS X on a FireWire external hard drive that I use whenever I want to work with music, however I can't get my iBook to start up from it today. Worked fine this morning, but I can't seem to get it to run. I'm able to start up on the internal hard drive's OS X, but whenever I try to startup on the external drive, the apple will sit there for a while then turn into a circle with a slash.

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