Startup Problems

Not every problem you encounter is related to running applications. Sometimes trouble strikes before you even get that far. The following are examples.

Kernel Panic

When you see the cheerful, multilingual dialog box shown in Figure B-3 you’ve got yourself a kernel panic—a Unix nervous breakdown.

(In such situations, user panic might be the more applicable term, but that’s programmers for you.)

If you experience a kernel panic, it’s almost always the result of a hardware glitch—most often a bad memory (RAM) board, but possibly an accelerator card, graphics card, or USB hub that OS X doesn’t like. A poorly seated AirPort card can bring on a kernel panic, too, and so can a bad USB or FireWire cable.

If simply restarting the machine doesn’t help, detach every shred of gear that didn’t come from Apple. Restore these components to the Mac one at a time until you find out which one was causing OS X’s bad hair day. If you’re able to pinpoint the culprit, seek its manufacturer (or its Web site) on a quest for updated drivers, or at least try to find out for sure whether the add-on is compatible with OS X.


This advice goes for your Macintosh itself. Apple periodically updates the Mac’s own “drivers” in the form of a firmware update. You download these updates from the Support area of Apple’s Web site (if indeed OS X’s own Software Update mechanism doesn’t alert you to their existence).

Figure B-3. A kernel panic is almost always related to some piece of add-on hardware. And look ...

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