Bootcamp Windows Partition Won't Boot After Accidentally Changing Boot-up Partition

Discussion in 'Boot Camp & OS Virtualization on Mac' started by JordanSimps, Aug 13, 2013.

  1. JordanSimps

    JordanSimps
    uix_expand uix_collapse
    Registered

    Joined:
    Aug 13, 2013
    Messages:
    1
    Likes Received:
    0
    I was messing around with the startup partition on my Windows 7 partition on my Mac and accidentally changed it to the Mac OS X partition. So when I boot the Windows 7 partition it says the error message "Missing Operating System". This error also shows up when I try to boot the Windows 7 DVD from the Mac drive selector screen. My question is how do change the boot partition on my Windows 7 partition if the partition won't even boot? I really don't want to install a new Windows 7 partition.

    Mac Specifications:
    Type: Mac Pro (Mid 2012)
    Processor: 3.33 GHz 6-Core Intel Xeon
    Memory: 32 GB 1333 MHz DDR3 ECC
    Graphics: ATI Radeon HD 5770 1024 MB
    Software: OS X 10.8.4 (12E55)
     
  2. DeltaMac

    DeltaMac
    uix_expand uix_collapse
    Tech

    Joined:
    Jun 20, 2001
    Messages:
    8,603
    Likes Received:
    110
    Boot to your Win7 installer DVD, and run the Startup Repair option.
    http://windows.microsoft.com/en-us/...ns#what-are-system-recovery-options=windows-7

    You said that you also get "Missing Operating System", even when booting to the installer DVD?
    Try that again, but with this method:
    insert the win 7 installer DVD, then shut your Mac Pro off. You can hold the power button for 5 seconds - or if you are successfully booted to OS X, you can just shut down normally.
    Press and release the power button, and immediately hold the C key on your keyboard. That should force your Mac to boot to the Win 7 DVD. Follow the on-screen tips to get to the Startup Repair choice, and continue with that.
     

Share This Page