Fix 1
Start off Apple CD/DVD
Startup Key: C
1 Insert a Mac OS X Install disc.
Tip: Hold down the mouse button while you
turn on your Mac to open the CD tray.
2 Hold down the C key while you turn on your
Mac. Let go when the gray Apple appears.
3 Mac OS X 10.2.x through 10.3.x: Choose
Installer > Open Disk Utility.
Mac OS X 10.4.x: Choose Utilities > Disk Utility.
4 Select your hard drive icon on the left and
click Repair Disk in the First Aid tab.
5 When your disk reports no errors, click Repair
Disk Permissions.
6 Reboot your Mac without holding any keys
during startup.
Tip: In additional to Apple’s tools, consider
purchasing Disk Warrior from alsoft.com.
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Fix 2
Target Disk Mode
Startup Key: T
When other techniques don’t work, Target
Disk Mode lets you access your Mac’s hard
drive from another computer.
This lets you perform additional diagnostics,
repairs, or backup important work files.
1 Hold down the T key while you
turn on your Mac. Let go when
you see a FireWire icon on the
screen (shown here).
2 Connect the troubled Mac to a
good Mac via a FireWire cable.
3 Open Disk Utility on the good Mac (located
in Applications/Utilities).
4 Select the troubled Mac’s disk icon on the left
and click Repair Disk in the First Aid tab.
5 If possible, recover or backup important data
files if the troubled Mac’s drive is visible on
the good Mac’s desktop.