My MacBook Is Rebooting Randomlyby James Wright
Mac OS X has a number of security and power features that let you customize how your laptop is secured and saves energy. If your MacBook is randomly restarting, this can be the result of a change in some of these settings. Alternatively, this can be a sign of deteriorating hardware, such as your logic board, or a system flaw.
Analyze the Problem
If your MacBook is restarting itself randomly, there are two different ways it can be doing this. The first is by automatically closing down all programs, logging you out, then restarting. The second is by shutting down instantly with no shutdown procedure, then rebooting. The latter is much more prominent in cases of actual hardware failure, and if maintenance attempts don't work, you will need to bring your laptop in to an Apple store.
Check Security Settings
A Mac's security settings allow you to set a certain time period of inactivity after which you will be automatically logged out. In some cases this has caused laptops to restart, so try disabling this option in your security settings. To do this, open System Preferences, open Security and Privacy and then click the General tab.
Repair Disk and Permissions
If a system error is causing your laptop to randomly restart, you may be able to fix it by using Mac's Disk Utility, which can repair many different types of errors and permission inconsistencies. From your Applications folder, open the Utilities sub-folder and double-click Disk Utility. Click your hard drive's name on the left sidebar, then click "Repair Disk Permissions." When this is done, click "Verify Disk." If the scan finds any errors, you will be able to click "Repair Disk."
Keep Your Laptop Cool
Most laptops have a safety mechanism to prevent internal damage from overheating, and the MacBook is no exception. If it gets too hot, it will shut down automatically to prevent any more heat from building up. Make sure you are using your laptop in a cool area and that none of the vents are blocked. If possible, set it on a table or desk to ensure proper air flow.