How can i downgrade from osx 10.8 to 10.7

Discussion in 'OS X Mountain Lion (10.8)' started by ojc123, Feb 19, 2012.

  1. macrumors newbie

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    Feb 19, 2012
    #1
    I really need help removing mountain lion dev preview 1. its crashing everything... Please help
     
  2. simsaladimbamba

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    #2
    You do need to do a clean install from the 10.7 recovery partition.
    The following guide is for 10.6, but the same rules apply for 10.7 once you have booted from the Lion recovery partition.
    To create a Clean Install (formerly known as Erase & Install) of Mac OS X 10.6 Snow Leopard (the 29 USD Upgrade DVD is a fully working retail version of Mac OS X and does not need a prior installation of Mac OS X on the Mac), follow one of the following guides:

    OS X Lion: About Lion Recovery
    Lion Recovery Disk Assistant


    I guess, you haven't backed up anything before installing OS X 10.8 Mountain Lion?
     
  3. thread starter macrumors newbie

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    Feb 19, 2012
    #3
    i back up all the time, but the recovery partition is for mac osx 10.8 not 10.7. so how do i get the 10.7 recovery back
     
  4. simsaladimbamba

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    #4
    How do you backup? Time Machine or a clone?

    And have you deleted the Mac OS X 10.7 Lion recovery partition? Normally when one installs OS X 10.8 Mountain Lion on a Mac with a Mac OS X 10.7 Lion recovery partition, one has two recovery partitions and two OS X partitions.


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    Maybe have a look at Advanced Search to find many similar threads about downgrading from OS X 10.8 Mountain Lion to Mac OS X 10.7 Lion:
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  5. thread starter macrumors newbie

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    Feb 19, 2012
    #5
    im use time machine, and the only recovery partition is 10.8, i didnt delete the other one it seems as if this one has replaced it
     
  6. simsaladimbamba

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    #6
    from OS X Lion: About Lion Recovery
     
  7. thread starter macrumors newbie

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    #7
  8. simsaladimbamba

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    #8
    Do you have access to any other Mac with Mac OS X 10.7 Lion?
     
  9. thread starter macrumors newbie

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    Feb 19, 2012
    #9
    unfortunately not, i do however have snow leopard install disks
     
  10. simsaladimbamba

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    #10
    Did your Mac come with Mac OS X 10.6 Snow Leopard?
    If so, you can do the clean install that way and later re-download Mac OS X 10.7 Lion and install it.
     
  11. thread starter macrumors newbie

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    Feb 19, 2012
    #11
    yes it came with snow leopard.

    will my latest time machine backup work though?
     
  12. simsaladimbamba

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    #12
    Yes, it will work with your personal files and settings.
     
  13. thread starter macrumors newbie

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    Feb 19, 2012
    #13
    So I boot from the osx install disk?
     
  14. simsaladimbamba

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    #14
    Yes, just follow one of the two clean install guides in post #2.
     
  15. macrumors 68000

    maril1111

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    #15
    yes exactly
     
  16. Nielsenius, Feb 19, 2012
    Last edited: Feb 19, 2012

    macrumors 6502a

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    #16
    I attempted to downgrade from 10.8 to 10.7 yesterday. I failed miserably. I believe that 10.8 upgrades the EFI firmware (on the logic board). I believe this is the case because the boot menu (hold alt at chime) has an added "Select Network" option. I could not boot into 10.7. I could only boot to 10.8 and Windows. Anybody telling this guy to "just boot from install disk" doesn't know what they're talking about in this situation. I tried reinstalling Lion three times! Never was I successful in getting Lion to boot (both Time Machine restore and fresh install from DVD).

    I think the only way to successfully downgrade from 10.8 to 10.7 is to download the latest EFI firmware update from http://support.apple.com/downloads/ and update the firmware manually through 10.8 and then downgrade via backup or fresh install. This is only a theory (I'm sticking with 10.8 for now).
     
  17. macrumors G3

    roadbloc

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    #17
    And this is why Mountain Lion is a Developer Preview.
     
  18. macrumors 65816

    Partron22

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    #18
    I'm not having any trouble booting my choice of 10.6, 10.7, or 10.8.
    I've got a "Recovery HD" on my 10.7 drive, and on my 10.8 drive. I suppose it's possible that the two having the same name could cause problems if you try to put them both on the same physical disk.
     
  19. macrumors regular

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    #19
    What exactly is it that is crashing? Not many other people are complaining about significant amounts of crashes.
     
  20. macrumors member

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    Jun 11, 2011
    #20
    I just thought I'd throw it out there as a systems administrator and app developer, after expirementing with DP1 on a trial computer for an extended period of time, I thought it stable enough to try on my MBP as well. All in all it was very stable, being that they didn't redesign the core of the OS I wasn't expecting a whole lot of problems. One major thing I did notice is that for some reason java was completely broken in chrome. No matter how many complete reinstalls of chrome or java I did, it wouldn't recognize.

    As for the downgrading question from time machine......

    I tried SO many things and all seemingly failed. It wouldn't downgrade no matter what I did. Here are the steps I had to take to make the downgrade successful:

    1. I burned a flash drive copy of lion (full so that I didn't have to download it... they exist.) and booted off that. I completely reformatted the Macintosh HD and reinstalled on that.
    2. After it succeeded, I booted and ran updates including EFI and Recovery HD updates. I then rebooted and booted to the newly repaired Recovery HD.
    3. I chose to restore from time machine and chose my latest backup. After it 'completed', it rebooted but just hung on the boot screen as has been a problem with time machine complete restores.
    4. I booted off my lion flash drive again and chose to reinstall lion on Macintosh HD, this time without using disk utility to reformat it first.
    5. After the reinstall completed, it rebooted and my OS was with the successful time machine restore.
    6. I had to run updates back to 10.7.3... but other than that everything appears to be normal.

    Thought I'd share for anyone struggling with this.
     
  21. macrumors 68000

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    #21
    I am not sure if you can do a time machine backup in snow leopard using a backup created in lion. Also, if you got Mountain Lion, you should pretty easily be able to re-download the Lion install since you have a developer license. Just download that and create an install DVD with it.

    Thats all presuming the firmware issue doesn't prevent you. I am not sure about that.
     
  22. macrumors 604

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    #22
    I hate it when people who don't know what they are doing fool around with betas and developer previews and then come screaming here when something goes wrong, very wrong.
     
  23. simsaladimbamba

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    #23
    But that is the human condition. Curiosity and ignorance almost always go hand in hand, strangely enough.
     
  24. macrumors 68030

    Krazy Bill

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    Dec 21, 2011
    #24
    This happens with every developer release. :D

    Why on god's good earth would anyone throw a beta OS onto a perfectly working system? :eek:
     
  25. macrumors member

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    Jun 11, 2011
    #25
    And that's Your opinion. Mine on the other hand, is this:

    The only reason I got to where I am today after 4 years in a computing program and all the way through my masters is because when I was a kid I took the time to screw up my system. I was constantly breaking this or that, whether it be on Mac, PC, or some flavor of linux. What made me great at IT support and systems administration was that I knew how to navigate problems and fix things others didn't. It was for that reason I installed on my main laptop as well, because I knew that if it Was stable enough, great. If not, I'd have a challenge getting my time machine to restore back. Granted with the simplicity Apple usually puts into their products I didn't expect to have This much of an issue with time machine, but at the end of the day I'm back on 10.7.3 running an image from friday.

    So judge all you want, but some of us have methods to our madness :cool:
     

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