Mac OS X doesn't need more of a troubleshooting, as there are very few chances of getting it corrupted. But in case if it runs into complex issues, then you'll need to restart your Mac in recovery mode, in order to resolve complex problems. Recovery Mode deals with disk permissions, reinstalling your OS X, and other technical stuff, which shouldn't be done if you aren't facing any issues.
Entering the recovery mode on Mac is pretty easy; the hard part is to deal with the problem. Here we will explain step-by-step on how you can get your Mac into Recovery Mode, just head south for complete details.
How to Start your Mac in Recovery Mode
Step #1. If your Mac is already ON, then go to Apple Menu and Restart.
Step #2. You'll need to be real quick while doing this step. Press and hold Command+R as soon as you hear the startup chime.
Step #3. Keep them pressed until you see the Apple logo.
If you have done it perfectly, you'll be in the recovery mode. In case you are presented with a login window, then you'll need to repeat the process, as you weren't quick enough to press the keys.
One more thing you'll need to consider, that is to use the built-in keyboard of your Mac. Many times, keystrokes aren't registered with other keyboards. Once you are in Recovery Mode, you might need to connect your Mac to the internet, as it needs to send your serial number to Apple servers.
That's it; you should have safely landed in the Recovery Mode by now.