Bootcamp Windows 8.1 Missing after Yosemite Upgrade

Good to see the NTFS Header. Please reboot and re-run the dd command to make sure you can see the NTFS header.

If you need exact steps for Step 5, please post back.

Step 5 example...

You need to create the Hybrid MBR. Here is an example...

sudo gdisk /dev/disk0

GPT fdisk (gdisk) version 0.8.10

Warning: Devices opened with shared lock will not have their

partition table automatically reloaded!

Partition table scan:

MBR: hybrid

BSD: not present

APM: not present

GPT: present

Found valid GPT with hybrid MBR; using GPT.

Command (? for help): p

Disk /dev/disk0: 490234752 sectors, 233.8 GiB

Logical sector size: 512 bytes

Disk identifier (GUID): 59BDFEEB-1EB4-4529-94FE-3CBC2C3CD513

Partition table holds up to 128 entries

First usable sector is 34, last usable sector is 490234718

Partitions will be aligned on 8-sector boundaries

Total free space is 2604 sectors (1.3 MiB)

Number Start (sector) End (sector) Size Code Name

1 40 409639 200.0 MiB EF00 EF

2 409640 401060383 191.0 GiB AF05 Macintosh HD

3 401060384 402329919 619.9 MiB AB00 Re

4 402331648 490233848 41.9 GiB 0700 Microsoft basic data

Command (? for help): r

Recovery/transformation command (? for help): h

WARNING! Hybrid MBRs are flaky and dangerous! If you decide not to use one,

just hit the Enter key at the below prompt and your MBR partition table will

be untouched.

Type from one to three GPT partition numbers, separated by spaces, to be

added to the hybrid MBR, in sequence: 2 3 4

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): AF

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

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

Enter an MBR hex code (default AB): AB

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

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

Enter an MBR hex code (default 07): 07

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

Recovery/transformation command (? for help): w

Final checks complete. About to write GPT data. THIS WILL OVERWRITE EXISTING

PARTITIONS!!

Do you want to proceed? (Y/N): y

OK; writing new GUID partition table (GPT) to /dev/disk0.

Warning: Devices opened with shared lock will not have their

partition table automatically reloaded!

Warning: The kernel may continue to use old or deleted partitions.

You should reboot or remove the drive.

The operation has completed successfully.

Now Reboot and verify the output of fdisk again.

Is it working after the Hybrid MBR was recreated? If yes, please switch between Windows and OSX and verify it works in both direction. Please take a backup of Windows and OSX.

Mr. @Loner T. Thank you very much... I followed your advice here and finally got it going. My windows partition is finally up and running.

The disconnect for me was that start/end had to come from a partition that could not be opened, rather than the one that could. I finally noticed it yesterday.

What Testdisk finds, is normally a "lost" partition. It will not show up in the GPT. If you found your files and used the correct start/end, Windows should come up as it did in your case. Very nicely done.

As I was having quite the same problem (5 gpt partitions resulting in the last one being omitted), I tried that solution too, but instead of only loading one partition, I skipped the recovery partition in MBR. Unfortunately, when writing the changes to disk, I got the following information "GPT data structures destroyed! You may now partition the disk using fdisk or other utilities.". Not great. No GPT partition anymore. I have been able to use gdisk again to convert MBR to GPT. Hope it's fine. I'm doing a backup of the volume before restarting. Is there something I can check before restarting?

Please verify your GPT by sudo gpt -vv -r show /dev/disk0.

Thanks for the reply. I checked the partitions using Partition Inspector. Everything seems fine. My backup will be finished in a couple of minutes so I'll be able to check. But by looking at my terminal session, I realized that I made a huge mistake. Instead of using command h to create the hybrid MBR, I used command g. I thought that this command was to create the hybrid MBR from the GPT, with the possibility to modify it before applying. Didn't understand that it was to replace the GPT by a MBR only partitioning. Should have looked at help on Internet before doing this.