How to Force Reboot a Frozen Mac
Though Macs are known for being stable and experiencing considerably fewer crashes and system freezes than some of the competition, the reality is that sometimes stuff still happens. Typically it’s just an app that crashes or freezes up, remedied with a force quit and relaunch, but on rare occasions the Mac will freeze entirely, with OS X becoming completely unresponsive to anything, from keyboard input to even the inability to move a cursor. This is often accompanied by fans blazing quite loudly, demonstrating a truly frozen Mac, and when this happens the computer is basically stuck in that state until you intervene.
Intervening is best done by forcibly restarting the frozen Mac, and that’s exactly what we’re going to cover here. With a truly frozen computer, you’ll actually be forcing it to shut down and then booting it again, as the traditional power shortcuts don’t work and aren’t registered.
How to Force Restart Any Frozen Mac with the Power Button
This works nearly the same on any modern Mac, with the difference being whether the Mac has a physical power button on the back of the machine or if it’s like the MacBook line, where the power button is on the keyboard. In both instances, a force reboot is basically forcing the Mac to shut down, then starting as usual. Again, this is only needed in extreme situations where a Mac is completely frozen with all possible interaction and input devices frozen and unresponsive.
Forcibly Rebooting a MacBook Air & Retina MacBook Pro
If the Mac has a power button on the keyboard, like all modern MacBook laptops do, this is how you forcibly reboot it:
- Hold down the Power button on the keyboard until the MacBook shuts down completely, this may take 5 seconds or so
- Wait a few seconds then hit the Power button again to boot the Mac
Force Restarting MacBooks with SuperDrives & Physical Power Buttons
For the older MacBook and MacBook Pro models which carry an eject key and a SuperDrive, the Power button is located on the upper right corner of the open Mac. The procedure is otherwise the same as above.
Forcibly Rebooting an iMac or Mac Mini
Unlike laptops, desktop Macs don’t have a power button on the keyboard, instead the power button is a physical button located on the back of the Mac.
- Press and hold the button on the back of the computer until the Mac turns off, wait a few seconds, and then press the button again to initiate system start
The iMac power button is located on the lower corner at the back of the computer, it shows the familiar power logo, but you can usually find it just by feeling around too.
Regardless of which Mac you have, the Mac should now boot as usual.
Macs can freeze for a variety of reasons, but if you recently installed new RAM on the computer, you may want to run a memory test to verify that it’s not bad RAM. If that checks out and the freezes are quite rare, it’s probably not something to worry about, but if the computer is constantly freezing up, you’ll likely want to back it up and get it looked at by Apple Support or a technician to be sure that there aren’t other hardware failures.
Note: some Macs and versions of OS X have an ‘automatically restart if Mac freezes’ option, though it has disappeared in recent versions of Mac OS X. If you do have that option and use it, you’ll likely never encounter a true freeze, the Mac will suddenly reboot, seemingly at random instead.