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Bootcamp disk issue

Hello Everyone,


I didn't install Yosemite yet (I saw Bootcamp issue related to it lately so I stayed with 10.9.5 Mavericks) but it seems that my Bootcamp was swept away. I cannot see Bootcamp disk in disk utility, it is replaced by the name disk0s3.

I didn't do anything special or using my computer lately so I don't know how the disk is corrupted.

I can't see the bootcamp icon anymore when starting my computer (Late 2013 macbook pro retina).


I'm downloading again the bootcamp installation in an USB drive so that I hope I can use the repair option from windows installation. Is it the right thing to do?

Can I use the Loner T method for repairing corrupted bootcamp after Yosemite installation (even it's not related to my problem the "symptoms are quite similar fem what I've read)?

Can you help through this, please do not hesitate to ask me more info. I have little knowledge on Mac.

I have important data for work on my Windows session and I will highly appreciate if you can help me through this.


Thanks ahead,

Jonathan

MacBook Pro (Retina, 15-inch, Late 2013), OS X Mavericks (10.9.5)

Posted on May 31, 2015 5:02 AM

Reply
21 replies

Jun 1, 2015 8:54 AM in response to MagicJonSon

This is normal and expected for the second MS Data. You cannot have two partitions be valid the same time. Your is a special case, because you do not have a Recovery HD. Please ensure that you use the following commands carefully, and stop when you see any error messages. You can safely ignore suspicious MBR messages.


Please read the entire message before you get started. You must install GPT Fdisk on your Mac - http://sourceforge.net/projects/gptfdisk/ .


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 '+' 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. 3 (part 3)
  5. N (new part)
  6. 3 (part 3)
  7. 389083136 - Start offset in bytes (start point for Bootcamp part)
  8. +588019712 - 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
  7. Y (Good for GRUB question)
  8. N (part 2 boot flag)
  9. Y (part 3 boot flag make NTFS bootable partition)
  10. O (print current Hybrid MBR)
  11. W (Write the new MBR)
  12. Y (Yes! write the new MBR)
  13. 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 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.

Bootcamp disk issue

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