My MacBook Pro does not boot! Here are the steps that I used to fix it, as a note to myself and to all in the same unpleasant situation.
A foreword: these steps are things that you can try in a specific case where a MacBook pro does not boot. Read the description and see if your machine is in the same situation: there’s a good chance that you might be able to recover. However if your MacBook is not booting for another reason the solution might well be a different one.
From a completely turned off computer press the power button: the screen stays black, with no backlighting, the power LED does one “breathing” and then stays solid on; the startup noise from the DVD drive can be heard, but not the typical chime of OS X booting; the fans are on, at normal speed. This happens on a MacBook Pro 15”, Early 2011 model.
What causes the problem is turning off the machine with the power button pressed for 5 seconds, while the OS was not responding or for any other reason. No matter what the machine is doing, 5 seconds of power button press will turn it off.
If you are already thinking of shelling out another 2K+ don’t panic and try one of these solutions.
If this is not working after 10 seconds of reattaching the cable, you’ll have to try another method. This worked for me the first time, but not the second time it happened.
These steps worked for me the second time:
At this time it will come up as normal.
If still your MacBook Pro does not boot try this as a last resort and only if you’re confident of what you’re doing and you have previous experience of working with computer internals:
If still your MacBook Pro does not boot try again with the first two solutions and resetting the SMC:
You might see magsafe LED momentarily turn green, and then go back to orange, assuming your battery was not full: this indicates a successful SMC reset. I did this several times before discovering solution 2.