Ian.paine

Q: Help - Windows partition has vanished after OSX updates.

Unsure what has happened here, but I can no longer boot to Windows Partition?

 

Looking at another thread it was suggested to run the following:

 

mac-mini:~ ianpaine$ diskutil list

/dev/disk0

   #:                       TYPE NAME                    SIZE       IDENTIFIER

   0:      GUID_partition_scheme                        *1.0 TB     disk0

   1:                        EFI EFI                     209.7 MB   disk0s1

   2:                  Apple_HFS Macintosh HD            250.8 GB   disk0s2

   3:                 Apple_Boot Recovery HD             650.0 MB   disk0s3

   4:       Microsoft Basic Data                         251.0 GB   disk0s4

 

mac-mini:~ ianpaine$ diskutil cs list

No CoreStorage logical volume groups found

 

mac-mini:~ ianpaine$ sudo gpt -vv -r show /dev/disk0

Password:

gpt show: /dev/disk0: mediasize=1000204886016; sectorsize=512; blocks=1953525168

gpt show: /dev/disk0: Suspicious MBR at sector 0

gpt show: /dev/disk0: Pri GPT at sector 1

gpt show: /dev/disk0: Sec GPT at sector 1953525167

       start        size  index  contents

           0           1         MBR

           1           1         Pri GPT header

           2          32         Pri GPT table

          34           6

          40      409600      1  GPT part - C12A7328-F81F-11D2-BA4B-00A0C93EC93B

      409640   489833880      2  GPT part - 48465300-0000-11AA-AA11-00306543ECAC

   490243520     1269536      3  GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC

   491513056   971778848

  1463291904   490231808      4  GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7

  1953523712        1423

  1953525135          32         Sec GPT table

  1953525167           1         Sec GPT header

 

mac-mini:~ ianpaine$ sudo fdisk /dev/disk0

Disk: /dev/disk0 geometry: 121601/255/63 [1953525168 sectors]

Signature: 0xAA55

         Starting       Ending

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

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

1: EE 1023 254  63 - 1023 254  63 [         1 -     409639] <Unknown ID>

2: AF 1023 254  63 - 1023 254  63 [    409640 -  489833880] HFS+

3: AB 1023 254  63 - 1023 254  63 [ 490243520 -    1269536] Darwin Boot

4: 0C 1023 254  63 - 1023 254  63 [1463291904 -  490231808] Win95 FAT32L

Mac mini, OS X Yosemite (10.10.3), null

Posted on May 28, 2015 12:03 PM

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Q: Help - Windows partition has vanished after OSX updates.

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  • Helpful answers

  • by Loner T,

    Loner T Loner T May 28, 2015 12:02 PM in response to Ian.paine
    Level 7 (24,227 points)
    Safari
    May 28, 2015 12:02 PM in response to Ian.paine

    Please post the output of the following

     

    diskutil list

    diskutil cs list

    sudo gpt -vv -r show /dev/disk0

    sudo fdisk /dev/disk0

     

    The "sudo" commands will prompt for your password, and it will not be echoed back. You may also see a warning about improper use of "sudo" and potential data loss due to "abuse" of the command.

     

    Do you have a Fusion drive?

  • by Ian.paine,

    Ian.paine Ian.paine May 28, 2015 12:05 PM in response to Loner T
    Level 1 (0 points)
    May 28, 2015 12:05 PM in response to Loner T

    No Fusion drive, no. I updated the first post with the output of those after reading another post.

  • by Loner T,

    Loner T Loner T May 28, 2015 12:13 PM in response to Ian.paine
    Level 7 (24,227 points)
    Safari
    May 28, 2015 12:13 PM in response to Ian.paine

    Please download the following two utilities which can help diagnose and fix partitioning issues.

     

    Testdisk is available at http://www.cgsecurity.org/wiki/TestDisk_Step_By_Step.

    GPT Fdisk is available at http://sourceforge.net/projects/gptfdisk/.

     

    Start Terminal from Applications -> Utilities -> Terminal and run Testdisk from the directory where it is downloaded. For example, I have it in the Downloads directory,

     

    ls ~/Downloads/testdisk-7.0-WIP/testdisk

    /Users/MyName/Downloads/testdisk-7.0-WIP/testdisk

     

    and I run it as

    sudo ~/Downloads/testdisk-7.0-WIP/testdisk /dev/rdisk0

     

    You should see a UI similar to https://imgur.com/a/PjmnK . You want to run a Quick Search first.

  • by Ian.paine,

    Ian.paine Ian.paine May 28, 2015 12:40 PM in response to Loner T
    Level 1 (0 points)
    May 28, 2015 12:40 PM in response to Loner T

    Screen Shot 2015-05-28 at 20.31.59.png

    pressing p on the top one

    Screen Shot 2015-05-28 at 20.38.41.png

    bottom one

     

    Screen Shot 2015-05-28 at 20.40.03.png

  • by Loner T,Solvedanswer

    Loner T Loner T May 28, 2015 12:49 PM in response to Ian.paine
    Level 7 (24,227 points)
    Safari
    May 28, 2015 12:49 PM in response to Ian.paine

    Leave your Testdisk display and start a new Terminal Window. You need to use the following steps.

     

    If you see any error messages during the following steps, please stop and post back here with the error message. The following steps have values from your Testdisk output (and you can verify) in Steps 7 and 8. Please notice the '+' sign in step 8.

     

    Rebuild GPT4 using start/end offsets

     

    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. 491513856 - Start offset in bytes  (start point for Bootcamp part)
    8. +1462009849  (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. Use defaults for other questions (like partition codes). The only values that need modifications are the Boot flags and step 10. Accept all other defaults that Gdisk offers.

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

     

    Here is sample Q&A for this section. Please notice the Press Enter/Return.

     

    Place EFI GPT (0xEE) partition first in MBR (good for GRUB)? (Y/N): Y

     

    Creating entry for GPT partition #2 (MBR partition #2)

    Enter an MBR hex code (default AF): Press Enter/Return

    Set the bootable flag? (Y/N): N

     

    Creating entry for GPT partition #3 (MBR partition #3)

    Enter an MBR hex code (default AB): Press Enter/Return

    Set the bootable flag? (Y/N): N

     

    Creating entry for GPT partition #4 (MBR partition #4)

    Enter an MBR hex code (default 07): Press Enter/Return

    Set the bootable flag? (Y/N): Y

     

    Test 1 - Does Bootcamp Volume show up in Finder?

    Test 2 - Can you see 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.

  • by Ian.paine,

    Ian.paine Ian.paine May 28, 2015 1:09 PM in response to Loner T
    Level 1 (0 points)
    May 28, 2015 1:09 PM in response to Loner T

    Looking promising.

     

    Test 1 - Does Bootcamp Volume show up in Finder? - YES

    Test 2 - Can you see files in Bootcamp Volume? - YES

    Test 3 - Can you select Bootcamp in System Preferences -> Startup Disk? - NO

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

  • by Ian.paine,

    Ian.paine Ian.paine May 28, 2015 1:25 PM in response to Ian.paine
    Level 1 (0 points)
    May 28, 2015 1:25 PM in response to Ian.paine

    It was not showing in Startup Disk due to something else I had installed to try and access that partition.

     

    Test 1 - Does Bootcamp Volume show up in Finder? - YES

    Test 2 - Can you see files in Bootcamp Volume? - YES

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

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

     

    Everything is working again! Thanks so much for your help!

  • by Loner T,

    Loner T Loner T May 28, 2015 3:45 PM in response to Ian.paine
    Level 7 (24,227 points)
    Safari
    May 28, 2015 3:45 PM in response to Ian.paine

    Excellent work.