Lost Bootcamp partition after upgrade to El capitan from an old 10.8.5 OS

• In Internet Recovery, we are going to remove and recreate GPT4.
  • Unmount disk - diskutil unmountDisk disk0
  • Remove old GPT4 - gpt remove -i 4 /dev/disk0
  • Add the correct GPT4 - gpt add -i 4 -b 118867968 -s 818829312 -t windows /dev/disk0
  • Reboot normally and check if you can see Windows files
• Install GPT Fdisk (http://sourceforge.net/projects/gptfdisk/)
• Post back when you are ready to correct the MBR.

GPT Fdisk has one-character commands. If you get an error from it about not being able to write to disk, you will need to temporarily disable SIP using csrutil in Local Recovery (Do not type text like this).

sudo gdisk /dev/disk0

p (print)

x (expert mode)

n (remove the current MBR)

o (print the default MBR for verification)

p (print)

w (write)

y (confirm write)

If you do not get any errors, reboot into Recovery and we can recreate the GPT4 entry.

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. Please see thesample Q&A as an example. These steps can be repeated if you make a mistake before you get to Step 12, otherwise start from Step 1 for these steps. Step 6 has numbers which are typed with a space between the numbers. Please see the sample Q&A before you execute these steps.

1. Sudo gdisk /dev/rdisk0
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.

mattia182 wrote:

so i will restart in internet recovery mode ... could you please tell me how to rebuild GPT4 ?

In Internet Recovery, we are going to recreate GPT4.

• Unmount disk - diskutil unmountDisk disk0
• Add the correct GPT4 - gpt add -i 4 -b 118867968 -s 818829312 -t windows /dev/disk0
• Run - diskutil repairDisk disk0
• Reboot normally and check if you can see Windows files

Yes, you will need to /rebuildBCD and /fixBoot. You may also need /fixMBR.

Can you post the output of

sudo gpt -vv -r show /dev/disk0

and the entire GDisk Terminal session?

Your GPT has

118867968  118108160      4  GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7

Your MBR has

*2: 07 1023 254  63 - 1023 254  63 [ 118867968 -  118108160] HPFS/QNX/AUX

but Testdisk shows the size of NTFS to be 818829312 sectors. Was the NTFS partition extended using any third-party partitioning tools? Also, notice the gap after GPT4, starting at 236976128 sector.

 118867968  118108160      4  GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7

  236976128  700726927      

The sizes - 118108160 + 700726927 = 818835087 , and your Testdisk layout (818829312 sectors) leaves 5775 sectors at the end of the GPT4.

Your MBR was not written to disk.

Warning! Secondary partition table overlaps the last partition by

700719137 blocks!

Try reducing the partition table size by 2802876548 entries.

looks to be the problem.

Can you run

diskutil repairDisk disk0

and post the output.

Looks fine. You no longer need to remove GPT4, so the new steps are.

In Internet Recovery, we are going to recreate GPT4.

• Unmount disk - diskutil unmountDisk disk0
• Add the correct GPT4 - gpt add -i 4 -b 118867968 -s 818829312 -t windows /dev/disk0
• Reboot normally and check if you can see Windows files

Can you see Windows files in macOS Finder?

Yes, try to recreate the MBR using the GDisk steps.