Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

Impossible to reinstall Mountain Lion on Macbook Air

Hi! Recently my mid 2011 air started crashing safari and then firefox. As per the forums I deleted add-ons and made sure that the latest software was downloaded from the app store. The 3 days ago the computer crashed and would not restart. It would not allow me into recovery either with an icon and contact apple support (World symbol with a warning ! and apple.com/support - 6002F). So...I installed 10.8.3 on a 1TB extenal hard drive and downloaded the installer program also (using my old Macbook pro). I then used this as a boot disk for the Air which was fine and I was able to then erase the Air's hard drive reformat (uncludind reducing the size of the main partition by a couple of gigs - as a support blog recommened. Then I was able to use the restore function form the external hard drive to try and do a web based reinstall of 10.8.3 - alas it spent 40mins downloading and then when I tried to install the OS it said it was corrupted and so I repeated that 3 more times to no avail (def of stupidity). Next I tried using the ext boot to load up and then downloaded 10.8.3 from the app store and then install it on my clean SSD (I had made sure that the disk did not need to be repaired) . Nope no joy here again an eternity download it and then the installation but at the end it just did not complete the install with some rediculous time to complete of 36hrs...eventually getting to 55mins then hung indefinitely. Having done this a few times with the same result I tried downloading a new 10.8.3 from the app store (while the computer was runing of the external boot drive) same result installation could be not completed.


Next I trieved my dusty snow leopard installation disk from a drawer and tried to use an external DVD drive to install this old OS with the hope that I could update later. Nope! Without the boot HD attached: the computer would not detect the ext drive...on restarts I pressed c button I held the alt button down - nothing the drive would fire up (PS I had checked the drive and disk worked on my MacBook and it did) and then shut down and the computer reverted to a grey screen with a pretty white apple logo! Next I tried booting up with the ext hard drive and installing snow leopard to the clean SSD - nope apple says no - you're not allowed do that while running snow lion as a boot disk! I'm 2 days at this now! I live in Ireland so there are no "genius" bars - in case that is a suggestion.


Currently I'm copying the contents of the Snow leopard disk to my clean SSD drive (having booted in Mountain Lion) for a hoot to see if the computer may boot directly from its own hard drive - I doubt this but I'm getting desperate. When that doesn't work my final throw will be to erase the ext hard drive and try install Snow leopard on it and use that as the boot drive then maybe Mr Apple will allow me to install Snow Leopard on the SSD!?


Someone please help!

MacBook Air, OS X Mountain Lion (10.8.3), 4GB 120 SSD

Posted on May 31, 2013 10:57 AM

Reply
4 replies

May 31, 2013 12:10 PM in response to GwayPaul

You won't get very far with the SL install. The EFI will not permit you to run an OS version that predates the version that the unit had, when it first shipped. This is purposeful, as it prevents you from using an OS that is without the requisite device drivers for that unit.


If you can't perform an Internet Recovery, then either you have a connection issue or a hardware issue. I would suggest you taing the unit in to a an Apple Store Genius Bar to see if you can alleviate whatever is inhibiting the IR.

May 31, 2013 2:16 PM in response to GwayPaul

At startup hold down the command+option+r keys until you see a globe on the screen. That will be the internet recovery, it might ask you for a password for your wifi connection so have that handy. From there you can reinstall lion as that is the version of os x that came on your air when new. Once that is completed you can upgrade to mountain lion from the mac app store once you log in with the same apple id you used when you bought mountain lion.

Jun 1, 2013 7:00 AM in response to GwayPaul

OK last evenings efforts were futile!


Thanks for the replies but as I said there is no apple store with in Ireland with a guru bar (whole country!) therefore not an option! Using my boot disk I can get into recovery and it will allow me to download M/L (again for 30-40mins) then it will not install it properly! I have tried some other options today including deleting the app store cache with the reg command: open $TMPDIR../C/ - didn't help my "This Copy of the Install OS X Mountain Lion Application can’t be verified". I just can not understand why it will not just let me reinstall software I have paid for on a computer I have bought...especially as it allowed me to creat a boot disk with that same software (which I am now using to type this!).


ANy further help would be hugely appreciated.


Thanks

Jun 1, 2013 7:19 AM in response to GwayPaul

First did you repartition the drive (or ssd in the air) as one partition with a format of mac extended (journaled) with a partition table of guid?


If not do that. ,If the install still fails then your only option is to call apple, have the serial number of that mac handy and order a replacement reinstall usb thumb drive for it. There is a small fee.

Impossible to reinstall Mountain Lion on Macbook Air

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple ID.