I would have expected to see something other than just the grey screen if it failed to find a working system folder.
How does it behave when you boot it from a Mac OS X installation disc?
How to replace the HD depends on what model of Macbook Pro you have.
On some it is just three screws and pull but on others it is a little more complicated.
Take a look at ifixit.com for information.
P
Hi guys,
A friend has given me his MacBook Pro to have a look at as it does not get past the grey screen. You get the opening sound and then the little wheel? going around in the middle of the screen, but nothing happens?? I have pressed the power button to start the computer and then
I pressed and held the Command (Apple) key and the "V" key (Command-V) for verbose mode. You get a nice long running screen in black and white with lots of information saying that this has failed, that has failed etc. (disc0sc: I/O error) so do I take it that the hard drive has stopped working?. Another question is "how do you remove the hard drive from a Mac?) and is it easy?
Any advice would be helpful. Bill.

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