Avoid using versions of OS X that are older than what came with your Mac. If you copy older system files from another computer to your Mac, or try to use startup disks designed for older computers, you might see one or more of the following:
- Your Mac doesn't start up, or you see a prohibitory symbol at startup
- You see a message that you're using an unsupported or incorrect version of OS X
- Your Mac doesn't respond to your trackpad, mouse, or keyboard
- Apps unexpectedly quit
- Your Mac doesn't sleep or wake
- You don't hear any sound from your Mac
- The fans in your Mac operate at a faster or louder speed
- The image on your display appears to "shrink" or has black bars around it, or appears tinted
- You can't use Bluetooth or Wi-Fi
If you're starting up from an external drive or network volume
If you can't start up your Mac from an external drive, make sure the version and build of OS X installed on the external drive is the same as, or newer than, what came with your Mac. You might see a prohibitory symbol, or a message that you're using an unsupported or incorrect version of OS X when the version of OS X on an external drive is incompatible with your Mac.
If the version of OS X installed on your external drive is newer than what came with your Mac, check the system requirements of that version to make sure it works with your Mac:
- OS X Lion (OS X 10.7)
- OS X Mountain Lion (OS X 10.8)
- OS X Mavericks (OS X 10.9)
- OS X Yosemite (OS X 10.10)
You can use OS X Recovery to install a version of OS X on an external drive that's compatible with your Mac.
If you're a network administrator setting up a NetBoot volume, you should configure your server to offer a compatible version of OS X to each Mac.
If you're restoring from a Time Machine backup
If you try to restore a Time Machine backup that was created on a different Mac, you might see a message that, "You can't restore this backup because it was created by a different model of Mac." Use Migration Assistant to move your personal information to your new Mac instead.
If you're installing OS X from a CD or DVD
Mac computers introduced before 2009 came with OS X Install or Restore discs. These discs were designed specifically for these older Mac models. If you see a prohibitory symbol when starting up from a disc, or an alert message that you're installing from an unsupported or incorrect disc, then you shouldn't try to use the disc with your Mac. If you need to reinstall OS X on your newer Mac, use OS X Recovery instead.