Safe boot doesn't work -- check default boot partition
A process needed to troubleshoot many Mac OS X 10.5.3 issues.
With the release of Mac OS X 10.5.3, many users are experiencing issues that are potentially soluble through the use of safe booting. Safe booting not only disables potentially problematic third-party software, but also performs default maintenance tasks that can result in a properly operational Mac after a single safe boot execution.
However, some users have discovered an inability to safe boot. MacFixIt reader Eric Francis writs:
"Since upgrading to 10.5.x I can't get Safeboot to activate and get me to the login window. It takes a long time to boot with shift key down as I expect with Safeboot, but it never gets to the login window, the computer restarts everytime. I have done an archive and install after running Disk Warrior and repairing permissions, still, no safeboot loging window. It just automatically restarts."
In some instances, safe booting can take an extraordinarily long time. You may even need to use an object to depress the Shift key while you are starting up then leave the system in order to invoke safe boot.
The problem could also be caused by a problematic RAID configuration. Try booting from a single drive rather than a RAID array, or temporarily disabling RAID capabilities (depending on your configuration) and safe booting again.
This issue ccan also sometimes be resolved by clearing caches. This is one of the fixes listed in our tutorial on troubleshooting problematic USB devices.
Use a tool like Cocktail, OnyX, MacPilot, or Tiger Cache Cleaner to perform a cache cleaning on your Mac. Start at the shallow levels (offered by some of the programs) and move onto the deeper routines.
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