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Open Firmware Password "hack" #

Mac OS X: The Missing Manual, Tiger Edition is a swell book for Mac newbies. But I'm surprised by the following passage found on page 448:
"[T]here is one way to secure your Mac completely: by using the Open Firmware Password program. ... This password is deadly serious and unhackable, and there's no back door. If you forget the Open Firmware password, you can't change the startup disk ever again. Even Apple can't help you out of that situation."

That's not exactly true. In fact, it's not really even close. Here's what Apple has to say about it in Technical Note TN2062: Guide to Creating Kiosks on Mac OS X:

"The Open Firmware Password will be reset if a user changes the amount of the physical memory in the machine and reboots."

So, the big scawy password can be reset by swapping out some RAM? Not exactly "deadly serious and unhackable" for anyone armed with a screwdriver.

UPDATE 1: Chuck Waggon had to experiment a good deal before this tip worked. After removing a stick of RAM, he had to reset the PRAM 3 times, holding down the Command and Option keys on the right side of the keyboard along with P and R.

UPDATE 2: As of the MacBook Air (Late 2010) and other 2011 Mac models, this workaround no longer works.

/mac | May 11, 2006

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