That means something is seriously wrong with the system, and it's preventing the machine from starting up. There's some information about this, as well as troubleshooting techniques, here:
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That means something is seriously wrong with the system, and it's preventing the machine from starting up. There's some information about this, as well as troubleshooting techniques, here:
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Also: Assuming you have Lion, try holding command-r at startup and using Disk Utility to verify/repair your disk.
charlie
I have the same problem. would you think that the solution is to wipe my hard drive?
Please help me...
My mac book air showing prohibited symbol
I want to take my data backup
What does the "prohibited" symbol at startup mean?