What to do when your Mac won’t start
If you’ve ever seen the dreaded ‘cancel’ symbol when starting up your Mac, then you know that sinking feeling. My Mac won’t start. Have I lost data? Can I get it working again?
Let me just say from the outset, that it is super important to have a backup for your Mac. Apple’s Time Machine is great for this, and if you don’t already, start using it immediately. Some of the advice that follows requires that you have a already have a Time Machine backup.
Recovery HD
Since Mac OS X 10.7 was released, every Mac has a hidden tool on it that can be used when your Mac won’t start. A separate section of your disk (called a partition) is set up and hidden away in the event that you need to repair your disk, reinstall your operating system, or perform a handful of other more nerdy tasks (which we may cover in a future article… let us know if that sounds fun). It’s called the Recovery HD.
So, your Mac won’t start. How do you use the Recovery HD to figure out what’s wrong? To start from the Recovery HD, hold the Command and R keys when powering on your computer until you see the Apple logo appear. At the end of the start up process, instead of your familiar desktop, you’ll first see a language selection screen. After you’ve chosen your language, a new window will appear, labeled ‘OS X Utilities.’
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