sandyblade
Level 1 (0 points)

Q: Missing Operating System after installing OS X Yosemite

Please help to give suggestion on how to recover my bootcamp after installing OS X Yosemite

sudo.png

Mac Pro, OS X Yosemite (10.10.1)

Posted on Nov 28, 2014 8:29 AM

by Loner T,Solvedanswer
Loner T Loner T
Level 7 (24,202 points)
Safari
A:

No. You have found your lost NTFS partition. Here is a table I use to validate that it is reasonable.

 

GPT 3 StartGPT 3 SizeGPT 3 EndNTFS StartByte OffsetNTFS SizeNTFS End
205722144126953620699168020706508873408105515001312580089

 

So your 'numbers' look as follows...

 

  1. Sudo gdisk /dev/rdisk0
  2. P  (print the full list of parts)
  3. D  (delete)
  4. 4  (part 4)
  5. N  (new part)
  6. 4   (part 4)
  7. 207065088
    - Start offset in bytes  (start point for Bootcamp part)
  8. +
    105515001
    (Size offset as opposed to End offset)
  9. 0700     (Windows part type)
  10. P           (print list of all parts just to see what changes will be made)
  11. W         (Write the new GPT)
  12. Y           (Yes! really write the new GPT)


This will delete and re-write the GPT partition info for /dev/disk0s4. 


Rebuild MBR to match the new GPT information thus resetting the Hybrid MBR

  1. Sudo gdisk /dev/disk0
  2. P  (Print list of parts)
  3. R   (Recover)
  4. H (chooses Hybrid)
  5. Partitions numbers to be hybridized: 2 3 4
  6. Y (Good for GRUB question)
  7. N (part 2 flag)
  8. N (part 3 flag)
  9. Y  (part 4 flag make bootable partition)
  10. W  (Write the new MBR)
  11. Y    (Yes! write the new MBR)
  12. Reboot


Test 1 - Does Bootcamp Volume show up in Finder?

Test 2 - Can you files in Bootcamp Volume?

Test 3 - Can you select Bootcamp in System Preferences -> Startup Disk?

Test 4 - If Test 3 is successful, select Bootcamp and Click Restart.


If you see a hanging underline cursor at the top left on a black screen, and it does not proceed further, you may need Windows Startup Repair or a tool called EasyBCD.



Posted on Nov 30, 2014 6:59 PM

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sandyblade

Q: Missing Operating System after installing OS X Yosemite

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  • Helpful answers

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  • by Loner T,Helpful

    Loner T Loner T Nov 30, 2014 5:47 PM in response to sandyblade
    Level 7 (24,202 points)
    Safari
    Nov 30, 2014 5:47 PM in response to sandyblade

    Will you be able to follow Missing Bootcamp Partition (with pastes!)? You will need Testdisk and GPT Fdisk. If you need links, let me know.

  • by sandyblade,

    sandyblade sandyblade Nov 30, 2014 5:52 PM in response to sandyblade
    Level 1 (0 points)
    Nov 30, 2014 5:52 PM in response to sandyblade

    TestDisk1.png

    TestDisk2.png

     

    TestDisk3.png

  • by sandyblade,

    sandyblade sandyblade Nov 30, 2014 5:57 PM in response to sandyblade
    Level 1 (0 points)
    Nov 30, 2014 5:57 PM in response to sandyblade

    Hi Loner T,
    I am trying to follow some of discussion, but I dont know much about bytes and offset. Can you help me about what should I do with this operation based on my screen capture:

    1. Sudo gdisk /dev/rdisk0
    2. P  (print the full list of parts)
    3. D  (delete)
    4. 4  (part 4)
    5. N  (new part)
    6. 4   (part 4)
    7. 1447020544 - Start offset in bytes  (start point for Bootcamp part)
    8. +506503161 (Size offset as opposed to End offset)
    9. 0700     (Windows part type)
    10. P           (print list of all parts just to see what changes will be made)
    11. W         (Write the new GPT)
    12. Y           (Yes! really write the new GPT)

     

    Especially what number that should I use

  • by Loner T,Helpful

    Loner T Loner T Nov 30, 2014 5:58 PM in response to sandyblade
    Level 7 (24,202 points)
    Safari
    Nov 30, 2014 5:58 PM in response to sandyblade

    Scroll down to the first MS Data entry and use 'P' to list files and look for familiar Windows files including 'System Volume Information'.

     

    Repeat this for all MS Data entries.

     

    Do not use left/right arrow/cursor keys in Testdisk since it alters  partitions.

  • by sandyblade,

    sandyblade sandyblade Nov 30, 2014 6:00 PM in response to sandyblade
    Level 1 (0 points)
    Nov 30, 2014 6:00 PM in response to sandyblade

    Here is my hexdump :

    hexdump.png

  • by sandyblade,

    sandyblade sandyblade Nov 30, 2014 6:04 PM in response to Loner T
    Level 1 (0 points)
    Nov 30, 2014 6:04 PM in response to Loner T

    The first ms data result:

    First MS Data.png

    Second MS data result:

    Can Found.pnga

    I can found all my bootcamp data here and also the system volume information.

  • by Loner T,

    Loner T Loner T Nov 30, 2014 6:04 PM in response to sandyblade
    Level 7 (24,202 points)
    Safari
    Nov 30, 2014 6:04 PM in response to sandyblade

    You have not found the correct NTFS header, so you cannot change the GPT yet. What does 'P' show within each MS Data partition?

  • by sandyblade,

    sandyblade sandyblade Nov 30, 2014 6:14 PM in response to Loner T
    Level 1 (0 points)
    Nov 30, 2014 6:14 PM in response to Loner T

    Hi Loner T,

    Here is the 1st until the 3rd print screen:

    1msdata.png

    2nd MsData.png

    3rd MsData.png

  • by Loner T,

    Loner T Loner T Nov 30, 2014 6:36 PM in response to sandyblade
    Level 7 (24,202 points)
    Safari
    Nov 30, 2014 6:36 PM in response to sandyblade

    Do not quit yet.

  • by sandyblade,

    sandyblade sandyblade Nov 30, 2014 6:38 PM in response to Loner T
    Level 1 (0 points)
    Nov 30, 2014 6:38 PM in response to Loner T

    Do you mean I need to wait on that screen?

  • by sandyblade,

    sandyblade sandyblade Nov 30, 2014 6:41 PM in response to Loner T
    Level 1 (0 points)
    Nov 30, 2014 6:41 PM in response to Loner T

    Do I need to do deeper search on the 1st Ms Data?     

  • by Loner T,Solvedanswer

    Loner T Loner T Nov 30, 2014 6:59 PM in response to sandyblade
    Level 7 (24,202 points)
    Safari
    Nov 30, 2014 6:59 PM in response to sandyblade

    No. You have found your lost NTFS partition. Here is a table I use to validate that it is reasonable.

     

    GPT 3 StartGPT 3 SizeGPT 3 EndNTFS StartByte OffsetNTFS SizeNTFS End
    205722144126953620699168020706508873408105515001312580089

     

    So your 'numbers' look as follows...

     

    1. Sudo gdisk /dev/rdisk0
    2. P  (print the full list of parts)
    3. D  (delete)
    4. 4  (part 4)
    5. N  (new part)
    6. 4   (part 4)
    7. 207065088
      - Start offset in bytes  (start point for Bootcamp part)
    8. +
      105515001
      (Size offset as opposed to End offset)
    9. 0700     (Windows part type)
    10. P           (print list of all parts just to see what changes will be made)
    11. W         (Write the new GPT)
    12. Y           (Yes! really write the new GPT)


    This will delete and re-write the GPT partition info for /dev/disk0s4. 


    Rebuild MBR to match the new GPT information thus resetting the Hybrid MBR

    1. Sudo gdisk /dev/disk0
    2. P  (Print list of parts)
    3. R   (Recover)
    4. H (chooses Hybrid)
    5. Partitions numbers to be hybridized: 2 3 4
    6. Y (Good for GRUB question)
    7. N (part 2 flag)
    8. N (part 3 flag)
    9. Y  (part 4 flag make bootable partition)
    10. W  (Write the new MBR)
    11. Y    (Yes! write the new MBR)
    12. Reboot


    Test 1 - Does Bootcamp Volume show up in Finder?

    Test 2 - Can you files in Bootcamp Volume?

    Test 3 - Can you select Bootcamp in System Preferences -> Startup Disk?

    Test 4 - If Test 3 is successful, select Bootcamp and Click Restart.


    If you see a hanging underline cursor at the top left on a black screen, and it does not proceed further, you may need Windows Startup Repair or a tool called EasyBCD.



  • by sandyblade,

    sandyblade sandyblade Nov 30, 2014 7:18 PM in response to Loner T
    Level 1 (0 points)
    Nov 30, 2014 7:18 PM in response to Loner T

    THanks a lot Loner T.

    All works fine.

    i Dont need windows repair.

  • by Loner T,

    Loner T Loner T Nov 30, 2014 7:30 PM in response to sandyblade
    Level 7 (24,202 points)
    Safari
    Nov 30, 2014 7:30 PM in response to sandyblade

    Very nice. One of the quickest discussions, thanks to you.

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