I want to install a fresh copy of OSX onto my Retina MBP, next to the one that it came preinstalled with.

I have created a 2nd partition using Disk Utility ready for the install, but have now found out that i have to do 'internet recovery' just to get a copy of Mountain Lion onto my machine.

Just to be clear - i dont want to backup using Time Machine then restore onto a new installation. I just want a clean, fresh installation of Mountain Lion, separate from my current one.

Can 'Internet Recovery' install to a 2nd partition? or would it hose my default one in the process?

By using Disk Utility to re-partition the SSD, have i blown away the recovery partition that is apparently hidden away on the disk when it comes out of the factory? (when i hold down the option key on boot, it gives me the option to boot into recovery so i assume its still there?)

What is the best way to create a fresh copy of OSX alongside the default one?

If have read that the App Store Mountain Lion is different from the pre-installed Retina one - is this still the case? and if i did download it, would i have to pay for it?


The best way is to boot into your current OS X install, and download the Mountain Lion installer from the Mac App Store. When the installer asks which drive to install to, select your second partition.

Internet Recovery is different to the Recovery HD partition.


As long as you have a valid Recovery HD partition, trying to boot into Internet Recovery will instead boot your Mac into standard recovery mode.

Both recovery modes download OS X anyway…

installing Mountain Lion from within recovery mode requires an Internet connection to download the actual OS.

…so I recommend using the Mac App Store to install Mountain Lion as I mentioned above.

Disk Utility shouldn't let you remove the Recovery HD partition unless you are in Debug mode. It is unlikely that you have accidentally deleted the Recovery HD partition, and since you can select it when holding alt to select a boot drive, I doubt very much that it's gone.

The App Store Mountain Lion installer is the universal installer capable of installing on any compatible Mac. There is no 'different installer' for Retina or otherwise.

  • Thanks for this info. I have read that the Retina version of Mountain Lion is different from that which comes from the App Store - is this still the case? Furthermore, if it came pre-installed, will i have to pay for it on the App Store? – Baldy May 19 '13 at 13:41
  • @Baldy All Mountain Lion versions are the same when they are downloaded. They do configure differently depending which computer model it is installed on, but the installer file is always the same. My Mac didn't come with Mountain Lion, and so when I go to the ML page on the App Store, I see a Download button that I can use to download the installer (I got an Up-to-Date App Store code). The installer that can be downloaded in this way can be told which partition to install to - I presume it is the same for the Recovery HD partition, however I am not certain since I have never tried it myself. – grg May 19 '13 at 14:16
  • @grgarside "Disk Utility shouldn't let you remove the Recovery HD partition unless you are in Debug mode": I erased a Recovery partition once by mistake without Debug mode... I think I selected the drive on the left (not a partition), then used the Erase tab... – Ashley May 20 '13 at 13:27
  • @Ashley Yes, but that is not partitioning a drive. "I have created a 2nd partition using Disk Utility ready for the install": this couldn't have removed the partition without Debug mode. – grg May 20 '13 at 15:54
  • @grgarside Yes, sorry -- I was responding to your sentence, forgetting about the question context. – Ashley May 20 '13 at 16:03

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .