AndyT0106

Q: Bootcamp Windows 7 disappeared after OS update last night...

After I updated to OS X Yosemite last night, my Windows 7 partition was gone.

I'm not able to see it when I press down OPTION during boot, but I do see a strange name "disk0s4" under disk utility.

Can anyone help me out here?

1111.png2222.png3333.png

MacBook Pro (Retina, Mid 2012), Windows 7

Posted on May 9, 2015 5:44 AM

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Q: Bootcamp Windows 7 disappeared after OS update last night...

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  • by 白崎つぐみ,

    白崎つぐみ 白崎つぐみ May 9, 2015 6:20 AM in response to AndyT0106
    Level 1 (5 points)
    May 9, 2015 6:20 AM in response to AndyT0106

    Mac OS X uses EFI partition table. I don't know if there is any utility to help fixing Mac partition table. I have encountered a similar problem, but mine is Windows cannot startup. If you have a startup disk with Windows PE installed, you may use that startup disk to boot your Mac, and use Command Prompt to view if there is any partition table error. (Boot Camp startup disk is also a good choice)

     

    If Windows partition is not visible under Windows PE, it is possible that the Windows partition table is damaged. Unfortunately, backing up partition table is not as easy as backing up personal data. So you still need to back up your whole disk before doing anything under partition table, because changing partition table outside Mac OS X will likely cause Mac OS X not bootable.

     

    According to the second screenshot you provided, it looks like the partition between index 3 and 4 is missing, and this should be your Windows partition.

     

    I am sorry I cannot give any usable methods to help you doing so, what I have done when facing to this is formatting disk, reinstalling windows.

  • by Loner T,

    Loner T Loner T May 9, 2015 7:51 AM in response to AndyT0106
    Level 7 (24,601 points)
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    May 9, 2015 7:51 AM in response to AndyT0106

    Can you use Bootcamp Broken after Resizing and OSX Update as a reference and download Testdisk and GPT Fdisk and start a Testdisk scan as shown in https://imgur.com/a/PjmnK ?

  • by AndyT0106,

    AndyT0106 AndyT0106 May 9, 2015 1:14 PM in response to Loner T
    Level 1 (0 points)
    May 9, 2015 1:14 PM in response to Loner T

    After spending almost half a day reading the threads you referred me to, I still don't get what steps I should take...

    Are you able to take me step by step?

    Your help is very much appreciated.

  • by Loner T,

    Loner T Loner T May 9, 2015 1:23 PM in response to AndyT0106
    Level 7 (24,601 points)
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    May 9, 2015 1:23 PM in response to AndyT0106

    1. Download Testdisk - http://www.cgsecurity.org/wiki/TestDisk_Step_By_Step.

    2. Run Testdisk - https://imgur.com/a/PjmnK

         a. You will need to run Deeper Search. Please post screen shots once a list of recoverable partitions is shown.

         b. Use 'P -List files' to look for a partition which has content similar to the following.

    Testdisk-GoodWindowsPartition.png

    3. Download GPT Fdisk - http://sourceforge.net/projects/gptfdisk/

         a. Run the steps using your specific start/end/size values and the highlighted solution steps.

         b. Test and Verify

  • by AndyT0106,

    AndyT0106 AndyT0106 May 9, 2015 5:41 PM in response to Loner T
    Level 1 (0 points)
    May 9, 2015 5:41 PM in response to Loner T

    Hi Loner T, this is what I got so far after it ran for a few hours.

    Please take a look and let me know, thanks!

    Screen Shot 2015-05-09 at 9.36.45 PM.pngScreen Shot 2015-05-09 at 9.39.03 PM.png

  • by Loner T,

    Loner T Loner T May 9, 2015 5:58 PM in response to AndyT0106
    Level 7 (24,601 points)
    Safari
    May 9, 2015 5:58 PM in response to AndyT0106

    Here is a table based on your Testdisk output using the first MS Data entry.

     

    GPT 3 StartGPT 3 SizeGPT 3 EndNTFS StartSector OffsetNTFS SizeNTFS EndSector Offset (MB)
    241963176126953624323271224323276856247001081490233848 0

     

    Please scroll down to the first MS Data entry. Use 'P' to list files and check against the example that I have posted. Do not use left/right arrow/cursor keys anywhere in Testdisk.

  • by AndyT0106,

    AndyT0106 AndyT0106 May 9, 2015 6:01 PM in response to Loner T
    Level 1 (0 points)
    May 9, 2015 6:01 PM in response to Loner T

    Is this what you need?

    Screen Shot 2015-05-09 at 10.01.06 PM.png

  • by Loner T,

    Loner T Loner T May 9, 2015 6:27 PM in response to AndyT0106
    Level 7 (24,601 points)
    Safari
    May 9, 2015 6:27 PM in response to AndyT0106

    You are looking at EFI partition. You need to check the first MS Data partition on the previous screen.

  • by AndyT0106,

    AndyT0106 AndyT0106 May 9, 2015 8:50 PM in response to Loner T
    Level 1 (0 points)
    May 9, 2015 8:50 PM in response to Loner T

    Is this the one?

    Screen Shot 2015-05-10 at 12.48.30 AM.png

  • by Loner T,Helpful

    Loner T Loner T May 10, 2015 5:40 AM in response to AndyT0106
    Level 7 (24,601 points)
    Safari
    May 10, 2015 5:40 AM in response to AndyT0106

    Yes, this is the one.

     

    Leave your Testdisk display and start a new Terminal Window. You need to use the following steps. You will need to install GPT Fdisk (aka Gdisk).

     

    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. Notice the '+' 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. 243232768 - Start offset in bytes  (start point for Bootcamp part)
    8. +247001081  - 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. H (chooses Hybrid)
    5. O (print current Hybrid MBR)
    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 AndyT0106,

    AndyT0106 AndyT0106 May 10, 2015 3:03 PM in response to Loner T
    Level 1 (0 points)
    May 10, 2015 3:03 PM in response to Loner T

    I followed thru the steps for the first section:

    Screen Shot 2015-05-10 at 7.00.11 PM.png

    Screen Shot 2015-05-10 at 7.00.32 PM.png

     

    But for the second part I got a warning saying I should repair the disk?

    Not sure what to do from here...

    Screen Shot 2015-05-10 at 7.03.04 PM.png

  • by Loner T,

    Loner T Loner T May 10, 2015 6:44 PM in response to AndyT0106
    Level 7 (24,601 points)
    Safari
    May 10, 2015 6:44 PM in response to AndyT0106

    Select '2' (GPT). Type 'q' to quit. Reboot and try the second set of steps again.

  • by AndyT0106,

    AndyT0106 AndyT0106 May 10, 2015 6:50 PM in response to Loner T
    Level 1 (0 points)
    May 10, 2015 6:50 PM in response to Loner T

    Did I do something wrong?

    Screen Shot 2015-05-10 at 10.49.51 PM.png

  • by Loner T,

    Loner T Loner T May 10, 2015 7:15 PM in response to AndyT0106
    Level 7 (24,601 points)
    Safari
    May 10, 2015 7:15 PM in response to AndyT0106

    No, you did not. I did. Can you switch steps 4 and 5 in the second set of gdisk steps? Type the 'o' command before the 'h' command.

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