11 Replies Latest reply: Feb 2, 2013 10:41 AM by Cattus Thraex
Mark Sanders Level 1 Level 1 (15 points)

I've been looking at different ways of getting a clean install of Lion on a machine that:

  • Has Lion already installed
  • Can boot into Recovery Mode

Is there a problem with the following, simple procedure:

  1. Boot into Recovery Mode with the usual cmd+R; connect to WiFi.
  2. Open Disk Utilities and erase/reformat the 'main' Partition on the Hard Disk
  3. Once a new, fresh partition has been created, get back into the main Lion Recovery dashboard
  4. Choose the Install Lion option pointed at the fresh partition.

 

Can someone confirm, please, that this should work, and that I won't be left with an empty partition on which Lion will refuse to re-install....?!

 

thanks

 

mark

 

PS If this makes a difference, I'm likely to need to do this on an iMac that was purchased with Snow Leopard, then updated to Lion in the usual App Store way; it's been reinstalled via Lion Recovery but not a clean install; the problems it has still persisted and I think it's time for a clean slate

  • 1. Re: Clean install of Lion in Recovery Mode - Easy?
    softwater Level 5 Level 5 (5,370 points)

    Yes, that will work, so long as you enter an AppleId that has purchased Lion when you click the 'Install Lion' button in Recovery Disk.

     

    I've done this literally dozens of times.

  • 2. Re: Clean install of Lion in Recovery Mode - Easy?
    Radiation Mac Level 5 Level 5 (4,635 points)

    Softwater, in reference to your above response, I've always thought, apparently in error, that in order to do a fresh re-install of Lion that if your older machine shipped with, say, Leopard that after erasing the harddrive's main OS Partition from Lion's Recovery Partition you first had to reinstall the Original OS from your Original Installation Disk in order to get the required system drivers, etc. that the older iMac requires, and then upgrade and update my way to a fresh upgrade to Lion.  You are saying that you having Lion currently on my older iMac I can literally boot into the Recovery Partition and Erase the main OS partition and do a clean install of Lion WITHOUT first installing the original OS?   (That would be too good to be true, if it's so!  And I've been wasting a lot of time.)

     

    Radiation Mac

     

    Message was edited by: Radiation Mac

  • 3. Re: Clean install of Lion in Recovery Mode - Easy?
    softwater Level 5 Level 5 (5,370 points)

    Radiation Mac wrote:

     

    I've always thought, apparently in error, that in order to do a fresh re-install of Lion that if your older machine shipped with, say, Leopard that after erasing the harddrive's main OS Partition from Lion's Recovery Partition you first had to reinstall the Original OS from your Original Installation Disk

     

    Nope, you don't need to do that. That would be entirely pointless.

     

    All the essential system resources required to install Lion are in the Recovery HD. Nothing else is required save for an internet connection to download all the packages required by the OS.

  • 4. Re: Clean install of Lion in Recovery Mode - Easy?
    Cattus Thraex Level 4 Level 4 (1,715 points)

    Apple has complicated things here, from reasons I cannot fully understand (perhaps from the basic assumption thast a complicted thing looks or seems or is considered great—a snobbish approach to life). The simplest, really simple, way to install Lion unto a fresh, formatted disk is to create a boot USB flash disk. It may take 20-30 minutes to do that, depending on your machine, but installation is fast from the moment of reboot.

  • 5. Re: Clean install of Lion in Recovery Mode - Easy?
    softwater Level 5 Level 5 (5,370 points)

    Slight correction to my reply to Radiation Mac. What you're doing is a clean install of your original OS then upgrading it to Lion.

     

    However, as I said, you don't need to do that. You can install Lion without a previous OS being present from the recovery partition in the way that the OP outlined in his first post.

  • 6. Re: Clean install of Lion in Recovery Mode - Easy?
    Radiation Mac Level 5 Level 5 (4,635 points)

    Thanks much for the good information, Softwater

     

     

    Radiation Mac

  • 7. Re: Clean install of Lion in Recovery Mode - Easy?
    Mark Sanders Level 1 Level 1 (15 points)

    Why do you think it is simpler to create a separate boot disk?

    I can see that you avoid the long (not that long) download, but don't you get updated install files straight off that way?

  • 8. Re: Clean install of Lion in Recovery Mode - Easy?
    softwater Level 5 Level 5 (5,370 points)

    It isn't, and its potentially problem-causing unless you know you've had one good, trouble-free install from that .dmg.

     

    I went that route the first time I downloaded Lion, had troubles with my first install and continued having troubles with every install afterward made from my USB installer. The light finally went on in my head that it was the original .dmg that I'd downloaded and saved to USB that was corrupt.

     

    Another point is that even if you have no problems with that .dmg, you'll be stuck with that version of Lion everytime and have to do laborious software updates. If you download directly you get whatever version is currently in the App store (10.7.4 right now).

     

    The only advantages I can see of doing it Cattus' way is if you either have a cap on your available downloads per month or a slow connection. Otherwise, not worth it, IMHO.

  • 9. Re: Clean install of Lion in Recovery Mode - Easy?
    Cattus Thraex Level 4 Level 4 (1,715 points)

    In some areas, the download in painfully long.

    A straitghtforward installation, if good, is better than a looooong download, even if the update must be applied too, and must be downloaded as well.

    I expressed my way to do things, you may disagree, if you have arguments. Or you may disagree without arguments—

  • 10. Re: Clean install of Lion in Recovery Mode - Easy?
    madridistagirl Level 1 Level 1 (0 points)

    I've tried this (multiple times now) on a macbook that was purchased with Snow Leopard but later upgraded to Lion. After the Lion download, my screen just goes back to the main recovery dashboard. And now when shut down and it starts up again, it only boots in recovery mode. Any idea why this might be happening or what I can do differently?

  • 11. Re: Clean install of Lion in Recovery Mode - Easy?
    Cattus Thraex Level 4 Level 4 (1,715 points)

    Your system got astray, from various reasons. I would erase the whole disk and reinstall from the scratch. I do hope you saved your files somewhere on an external drive. If not, your first step, and really your first step, would be to backup all your data via firewire cable unto another mac, which you need for this operation or use that mac as the server, to which an external backup disk is connected. If you have an aluminum 2008, which does not have firewire, then remove the disk, which is easy indeed, put it in an enclosure, backup your data, then proceed to a clean install.

    If you already have a good backup, there is not danger to erase the disk, In your situation, this is perhaps the best solution as your system has got so corrupt. The most important thing is to have a backup, then there are some other solutions. You need a second mac though, you cannot do this with a PC.