There isn’t much scarier than seeing your $1K+ Apple computer cease to function. Fortunately, you paid for quality hardware / software and restoring functionality is pretty straight-forward.
Indications that your mac isn’t (or won’t) boot include: a blinking folder icon with a question mark; an infinitely spinning wheel on the apple boot screen; or a frozen spinning wheel on the apple boot screen.
If you have any of these symptoms, the first thing that we are going to do is power off the mac completely. To do this, hold down the power button on the bottom left back of your iMac or the top right of your Macbook. Once it is fully off, turn it back on and hold CMD+R. This will boot you to recovery mode.
From here, you have access to OSX’s core system utilities. Of the options available, select Disk Utility.
In Disk Utility, on the upper right hand side you should see something labeled Macintosh HD. It might have another name depending on whether you or someone else has tinkered with your hard drive.
Click on that tab and then on the bottom right: click Verify Disk. Let that run its course and hopefully everything will come up green. If it doesn’t and gives you an error along the lines of “Backup your data and Reinstall OSX” you better do just that. It might give an error that says that the disk must be repaired. In that case, click the Repair Disk option and let it run. Once it finishes (hopefully successfully), click it again and make sure it comes up green.
Then, to the left, click Verify Permissions. I have never not seen it come up with errors. Once its done, click repair Permissions and let it run.
Now its time to try a reboot. Click the Apple symbol on the top left and click reboot. If it boots to OSX: YAY! If not, we aren’t going to give up that easily.
If that didn’t fix your problem and your verify disk came up green, you may have to reinstall OSX. Fortunately, because of the way that OSX is designed, it shouldnt wipe out any of your data. It will just reinstall system files. BACK UP YOUR DATA ANYWAY!
Get back into recovery mode and click Reinstall OSX. Depending on the OSX version you have, it may ask for iCloud / Apple ID credentials. Go ahead and enter those and continue on your merry way.
If that fails or it won’t let you reinstall, there is another option. Shut down your Mac and start it back up holding the ‘n’ key. Make sure you are connected to the internet! This will download a temporary recovery mode to your computer in the event that your recovery area is corrupted. Try the reinstallation from there.
If THAT doesn’t work, you are probably going to need someone’s disk, or if you are particularly crafty, you could make your own OSX boot media if you have access to another mac.
It’s rare that you would eventually need physical media but it is possible.
I hope that this helps some people get their mac’s back up and running again! Feel free to comment or contact us if you have any questions!