Bootcamp drive disappears after El Capitan upgrade

Install GPT Fdisk (aka gdisk). 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 (this is called offset notation). The text in parentheses is for informational purpose to describe the action being taken. Gdisk has one-character commands except when entering numbers.

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. 1241026560 ( - Start offset in sectors or the start point for Bootcamp part)
8. +713183225 ( - 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. 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.

Please post the output of

sudo gpt -vv -r show /dev/disk0

sudo fdisk /dev/disk0

I rebooted and can use the Option key to boot into Windows. Will go back into Mac OS later as I have a deadline.

Thanks so much!

Is there a lock icon on the System Preferences -> Startup Disk ?

Just wanted to weigh in with a +1 for Loner T.

I just installed El Cap on my way to installing Win 10 when *poof* Bootcamp found itself in the Witness Protection Program. Even though I had both Winclone and Windows images available, the Loner T solution was much more elegant, and effective.

I followed the process exactly as described, substituting my specific data where required, and it clicked on the first attempt. The only sidebar was turning off SIP as outlined here;

https://www.quora.com/How-do-I-turn-off-the-rootless-in-OS-X-El-Capitan-10-11

which was pointed out in gdisk as a necessary step. Other than that it went very smooth. Your mileage may vary, but it worked well for me.

Thanks Loner T, and good day to you sir.

flyby1023 wrote:

Thanks Loner T, and good day to you sir.

Good Day to you as well. Please ensure you have good backups of OSX and Windows. 😉

Does Recovery Disk show up when you hold Alt/Option during power up? Test Command+R and check if you see Recovery without a spinning globe.

Same situation here, having followed all the steps I've been able to get my Windows 10 partition to show up correctly again, but the recovery partition is no longer there beside OS X and Windows.

Does Command+R boot without a spinning globe in Local Recovery?

Sorry to hijack, but I have a question... How would I know what values I should substitute with? I've tried using dummy figures used by others, and this has helped bring up the windows icon during booting, but says "no operating system" when I boot from there. Perhaps a fault of using wrong values?

Any input appreciated.

Thank you!

slowpokealfa wrote:

Sorry to hijack, but I have a question... How would I know what values I should substitute with? I've tried using dummy figures used by others, and this has helped bring up the windows icon during booting, but says "no operating system" when I boot from there. Perhaps a fault of using wrong values?

The values to specific and unique to each individual. You cannot use values from someone else's Testdisk output. Can you start a new discussion and post the output of 'p' (List files) from Testdisk showing your Windows file structure? You can make your situation worse by using someone else's values. 😉