iMac Mac OS deleted by Windows 7

Discussion in 'iMac' started by valleyofthemac, Jul 24, 2013.

  1. valleyofthemac macrumors newbie

    Joined:
    Jul 23, 2013
    #1
    I hope this goes here instead of the Windows 7 sub-forum. Please let me know if it belongs there instead.

    Purchased second-hand mid-2011 iMac 21.5, that the previous owner had overwritten with Windows 7. It doesn't appear he used Boot Camp or iPartition, but rather recklessly installed Win7 right over the top of everything:

    * mid-2011 iMac (21.5)
    * starts up as grey screen, Mac startup sound
    * No Apple logo
    * 5 seconds later, initiates Windows 7
    * I purchased Snow Leopard install disc, installed Boot Camp on Windows, attempted to boot to Boot Camp, then directly from disc
    * Quickly learned MacOs is missing
    * The BootCamp mount merely repeats all of the above and goes to Windows
    * The direct-from-SnowLeopard-disc mount ("c" at start) did produce the black Apple logo and the dreaded 3 beeps, and nothing further

    I do have Apple OEM USB keyboard and mouse, but I don't have the iMac's original install discs, nor really anything other than the iMac itself. I do have a fairly old MacBook that has FireWire but not TBird. I have not tried target-to-disc yet, as my frustration level was high enough yesterday to walk away.

    This was a fairly inexpensive purchase, so I'm willing to try any suggestion. Thanks in advance from a new poster.
     
  2. Adam552 macrumors 6502

    Joined:
    May 30, 2006
    Location:
    Liverpool, UK.
    #2
    Can you boot onto Mac OS X Installation disc? Go into Disk Utility, check to see the partition setup. Just wondering if there's just 1 partition holding Windows on - and whether any free space is available. You may have to delete all the partitions and create a new one, install OS X on that. As last time I tried to resize a Windows partition, it made it unbootable.
     
  3. Anonymous Freak macrumors 601

    Anonymous Freak

    Joined:
    Dec 12, 2002
    Location:
    Cascadia
    #3
    If your Snow Leopard disc is a "Retail" disc, it likely won't work - the mid-2011 iMac requires 10.6.6 or above. You'll need a device-specific 10.6.6 disc, or a 10.6.7-or-later disc.

    Or, you can take it to an Apple Store and they could help you in getting Snow Leopard on. (Just tell them you want to get OS X back on so you can buy/upgrade to Mountain Lion, they'll help you out.)

    If you don't live near an Apple Store, try a local Apple-authorized reseller.

    If you know someone else with a Lion or Mountain Lion-compatible Mac, you could have them make you a Lion or Mountain Lion install disc from the download.
     
  4. macthefork macrumors 6502

    Joined:
    Feb 2, 2013
    #4
    Have you tried to boot holding down the "Option" key? Does it show a restore/recovery Partition (or an Mac OS partition)? If it shows a recovery partition, boot into that and try to restore the missing OS that way. If the HDD has been reformatted, this will not be available.

    If the above doesn't show any Mac OS or Recovery Partition, you could try the Target Disk mode from the Macbook. Both the iMac and the Macbook have Firewire. Cloning from one to the other may or may not work well, because of different logic board and GPU architecture between the computers. (running Combo Updates can sometimes fix this issue, though)

    The best thing to do would be to simply purchase and download Mountain Lion from the Apple store for $20.00.
     
  5. G4DP macrumors 65816

    Joined:
    Mar 28, 2007
    #5
    As that machine only shipped with Lion and nothing earlier, you will need to get hold of a Lion installer.

    http://support.apple.com/kb/sp623

    If you have it on the laptop you may be able to re-download the installer from the App Store. Place this on a USB stick or burn to DVD and then try to install.

    Although it may take a little longer it may be safer to burn to DVD and then start up the iMac holding down the D key.
     
  6. valleyofthemac thread starter macrumors newbie

    Joined:
    Jul 23, 2013
    #6
    These are all really good answers. Thank you all.:eek:

    "Or, you can take it to an Apple Store and they could help you in getting Snow Leopard on. (Just tell them you want to get OS X back on so you can buy/upgrade to Mountain Lion, they'll help you out.)"

    This was always Plan B, but your post prompted me to make an appt at Apple today. They could only get to it next week so that gives me four days to stay on Plan A.

    "Have you tried to boot holding down the "Option" key? Does it show a restore/recovery Partition (or an Mac OS partition)? If it shows a recovery partition, boot into that and try to restore the missing OS that way. If the HDD has been reformatted, this will not be available."

    This was worth a shot but it only offered me the Windows or the Snow Leopard DVD. Snow Leopard boots into black logo and three beeps. So no go.

    "If your Snow Leopard disc is a "Retail" disc, it likely won't work - the mid-2011 iMac requires 10.6.6 or above. You'll need a device-specific 10.6.6 disc, or a 10.6.7-or-later disc."

    I could smack myself in the head for not having deep-dived this info. So this must have been the first iMac product to ship with Lion. So I'm going to burn a Lion disc and try to boot from that. Then if that doesn't work, try to target from that per firewire from the MacBook.

    Will update again. Thanks all.
     
  7. macthefork macrumors 6502

    Joined:
    Feb 2, 2013
    #7
    Just for information, I have a mid 2011 iMac, and I do boot occasionally into a Snow Leopard Partition 10.6.8 (for music composition). So, even though it shipped with Lion, it will run the later versions of Snow Leopard.
     
  8. inodes macrumors newbie

    Joined:
    Jan 31, 2011
    #8

Share This Page