MacBook Pro shows circle with diagonal line
MacBook Pro shows circle with diagonal line
MacBook Pro, OS X Yosemite (10.10.1)
It means it can't find the operating system. And no MacBook Pro can run Mac OS X 10.3 or earlier.
The minimum operating system for any original MacBook Pro is some version of 10.4.4. Some later ones can only run 10.10.
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