Previous 1 25 26 27 28 29 Next 1,467 Replies Latest reply: Jun 20, 2015 10:52 AM by ManeeshAgarwal Go to original post Branched to a new discussion.
  • Christopher Murphy Level 3 Level 3 (555 points)

    For future reference, please don't delete the command you used to get the result. What you've provided are the commands for the SSD, which only contains the OS X and Recovery HD partitions. There is no Boot Camp/Windows partition on the disk. So need to repeat the commands with /dev/disk1 instead of /dev/disk0.

  • maghikal Level 1 Level 1 (0 points)

    Thank you!

    here's the hexdump

    sudo dd if=/dev/disk1 count=1 2>/dev/null | hexdump -C

    Screen Shot 2013-01-23 at 5.28.05 PM.PNG

  • Christopher Murphy Level 3 Level 3 (555 points)

    You did not provide the result from

    sudo fdisk /dev/disk1

     

    That you are getting the error you're getting tells me the hybrid MBR may be intact but you have bootloader problems that need to be repaired. Difficult to be sure without seeing the MBR.

  • maghikal Level 1 Level 1 (0 points)

    oh sorry i didn't realize you were respnding to someone else.


  • Christopher Murphy Level 3 Level 3 (555 points)

    OK look, there are currently THREE PEOPLE who are asking for help at the exact same time. So everyone needs to read the post header to know who is being talked to:  Jan 23, 2013 3:47 PM (in response to autnagrag)

     

    When I asked for fdisk results, it was for autnagrag.

  • Christopher Murphy Level 3 Level 3 (555 points)

    OK re: the hexdump. This seems viable but does not contain the error you're getting, so it's not a problem with the MBR bootloader. It could be a BIOS error (Macs use a CSM-BIOS for booting Windows), or it could be an ntldr problem. So I don't see any way around this other than to find a Windows repair disk, or install disk and try using Startup Repair. I know that Windows doesn't like being moved around to different hardware in particular it flat out won't boot if the CPU families are different.

  • maghikal Level 1 Level 1 (0 points)

    That makes sense. I went from a haswell i5 to an ivy bridge i7. I'll try the System Repair option and report back.

    Any reason why it works in Parallels, wouldn't that count as a completely new environment?

     

    Again Thank you for your help and sorry for the confusion earlier.

  • autnagrag Level 1 Level 1 (45 points)

    $ sudo fdisk /dev/disk1

    Password:

    Disk: /dev/disk1          geometry: 60801/255/63 [976773168 sectors]

    Signature: 0xAA55

             Starting       Ending

    #: id  cyl  hd sec -  cyl  hd sec [     start -       size]

    ------------------------------------------------------------------------

    1: EE 1023 254  63 - 1023 254  63 [         1 -  976773167] <Unknown ID>

    2: 00    0   0   0 -    0   0   0 [         0 -          0] unused     

    3: 00    0   0   0 -    0   0   0 [         0 -          0] unused     

    4: 00    0   0   0 -    0   0   0 [         0 -          0] unused

  • Gatormac2112 Level 1 Level 1 (0 points)

    Sorry Chris! Here is the updated info:

     

    Screen Shot 2013-01-23 at 4.00.44 PM.png

    Screen Shot 2013-01-23 at 5.55.02 PM.png

    Screen Shot 2013-01-23 at 5.55.58 PM.png

     

    Thanks for all your help!

  • Christopher Murphy Level 3 Level 3 (555 points)

    I'm not sure why you're getting the error you're getting at all because you don't even have a hybrid MBR on that disk, so that's why Windows won't boot. So you'll need to use gdisk to create a new hybrid MBR on disk1. Realize that every time you reboot, there is a change the physical disks swap designations between disk0 and disk1 so you have to check with diskutil list if you reboot, before making changes to the partition to make sure you're changing the correct disk.

     

    Also, you should do an fdisk command on the other disk, disk0, to see if it has a hybrid MBR that's causing confusion.

  • Christopher Murphy Level 3 Level 3 (555 points)

    Not sure. But you can use the dd + hexdump command on both disks and see if only one of them has bootloader code in that first sector. Only one disk should. If both disks have boot loader code, that might cause confusion becase Apple's CSM-BIOS is kinda dumb with a one track mind. It only expects to find and boot one Windows system, and isn't configurable like a real BIOS where you can choose what disk or partition to boot from.

  • Christopher Murphy Level 3 Level 3 (555 points)

    Yeah so you need to use gdisk on disk1 (the one with Windows on it).  You need to create a new hybrid MBR, adding partitions 2 3 4;  say yes to putting the EFI GPT first in the MBR; do not make partitions 2 or 3 bootable, do make 4 bootable. Write out the new partition with w command, and then reboot.

  • autnagrag Level 1 Level 1 (45 points)

    Thanks for the heads up about the instability of identity of disks 0 and 1.

     

    $ sudo fdisk /dev/disk0

    Password:

    Disk: /dev/disk0          geometry: 14593/255/63 [234441648 sectors]

    Signature: 0xAA55

             Starting       Ending

    #: id  cyl  hd sec -  cyl  hd sec [     start -       size]

    ------------------------------------------------------------------------

    1: EE 1023 254  63 - 1023 254  63 [         1 -  234441647] <Unknown ID>

    2: 00    0   0   0 -    0   0   0 [         0 -          0] unused     

    3: 00    0   0   0 -    0   0   0 [         0 -          0] unused     

    4: 00    0   0   0 -    0   0   0 [         0 -          0] unused     

    $

     

    So, I should reboot, and then verify which disk is 0 and which is 1, then use gdisk to "create a new hybrid MBR on disk1."

     

    That things be clear, is it my goal, after I study the menus of gdisk and restudy this long thread, to change the Bootcamp slice that is now disk1s5 per my first post so that it becomes "a new hybrid MBR on disk1?" That is to say, do I seek to change the characteristics of a thing that now exists? If it matters, this drive is on my MBP 7,1, OS X 10.8.2 (12C60)

  • Gatormac2112 Level 1 Level 1 (0 points)

    Thanks again Chris. One question before I try it: You stated not to make the third partition bootable, yet that is my bootable backup of OS X. Shouldn't I make it bootable?

  • Christopher Murphy Level 3 Level 3 (555 points)

    Absolutely not. The MBR active flag is only relevant for the Windows boot loader. OS X uses a completely different mechanism.

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