How to Re-Install OS X with Internet Recovery on a Mac.

Hello there, it’s been a productive morning here at Mission Repair! I have a little tidbit that is NOT NEW, but it’s super useful when you are in need and not a lot of people actually use this feature in the Mac. It’s called Internet Recovery, and it allows you to reinstall your software without any discs or external drives. You just need a wireless Internet connection.


The Software Reinstalling

In some rare situations, reinstalling OS X on a Mac may be required. This is made fairly easy as all modern Macs include the OS X Internet Recovery feature, which lets you reinstall OS X through a netboot type of mode that is accessed from the internet rather than a local drive. This is helpful in the event you need to reinstall Mac OS X because you need to replace the system software for whatever reason. Truth be told, we do a lot of system installations here at Mission repair for our customers because of file loss, corruption or once in a blue moon- a virus. Remember, we’re talking about Macs here.

To be clear, we’re going to focus on Internet Recovery here, but there are actually two modes of system recovery; one of which is based on a local Recovery disk partition, and the other which is called Internet Recovery, the latter being triggered if the Mac does not have a Recovery partition found or if booted directly into as shown in this walkthrough. Both of the recovery modes let you re-install OS X, but the version of OS X that is installed onto the Mac will be different depending on the type of recovery mode used. Specifically, the Recovery HD partition will re-install the most current version of OS X that is currently installed on the Mac, whereas Internet Recover will re-install the version of OS X that originally came with the Mac. That difference in how the two features works means you could theoretically use Internet Recovery to downgrade OS X to the version that shipped with the Mac, though there are better ways to do that if you have a Time Machine backup from the prior OS X release handy.

Internet Recovery requires internet access, that may be slightly obvious but it’s worth mentioning because if the Mac is unable to connect to a network then it will not be able to download the operating system. Whenever possible, you should back up the Mac with Time Machine before attempting this.

You can start the internet recovery reinstall process from either a shutdown Mac, or by rebooting the Mac. This process will be the same on any new Mac, be it an iMac, MacBook Pro, MacBook Air, etc:

1. Immediately after hearing the Mac boot chime, hold down Command+Option+R – if you see the Apple logo you waited too long and need to reboot and try again!
2. OPTIONAL: You may or may not see an option to join a wi-fi network, this depends on whether the Mac can access any saved networks from OS X or not.
3. When you see a spinning globe icon, Internet Recovery mode has been entered with a message saying it can take a while, a progress bar appears as the recovery functions are downloaded.
4. When finished downloading, you’ll see the familiar “OS X Utilities” screen, choose “Reinstall OS X” to begin the re-installation process of the Mac operating system!
5. Select the destination and complete the re-installation (or installation) of OS X as usual.

Installing and re-installing OS X through Internet Recovery is pretty easy, but do be aware that because everything is coming from Apple servers, it can take quite a while as the system restore features are downloaded locally, and then the version of OS X to install are also downloaded locally as well.

Again, this is not a new feature that just came out for the Mac…it’s well known in the tech world, and I thought that maybe you’d want to know about it too.

Take care, Ryan