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adamsouthern Author

Level 1

0 points

Bootcamp Broken after Resizing and OSX Update

Hello, so after updating to Yosemite 10.10.3, my bootcamp partition, which was previously resized, has become unbootable. I can't read the partition in finder and can't see it in Startup Disk. It, however appears as "disk0s4" in disk utility. I've posted some outputs of commands suggested in another thread. Hopefully this will help fix this issue.

Adams-MacBook-Pro:~ Adam$ sudo fdisk /dev/disk0

Password:

Disk: /dev/disk0 geometry: 30515/255/63 [490234752 sectors]

Signature: 0xAA55

Starting Ending

#: id cyl hd sec - cyl hd sec [ start - size]

------------------------------------------------------------------------

1: EE 0 0 2 - 25 127 14 [ 1 - 409639] <Unknown ID>

2: 03 25 127 15 - 1023 254 63 [ 409640 - 255104784] XENIX /usr

*3: 03 1023 254 63 - 1023 254 63 [ 255514424 - 1269536] XENIX /usr

4: 00 0 0 0 - 0 0 0 [ 0 - 0] unused

Adams-MacBook-Pro:~ Adam$ diskutil list

/dev/disk0

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *251.0 GB disk0

1: EFI EFI 209.7 MB disk0s1

2: Apple_HFS Macintosh HD 130.6 GB disk0s2

3: Apple_Boot Recovery HD 650.0 MB disk0s3

4: Microsoft Basic Data 70.0 GB disk0s4

Adams-MacBook-Pro:~ Adam$ sudo gpt -vv -r show /dev/disk0

gpt show: /dev/disk0: mediasize=251000193024; sectorsize=512; blocks=490234752

gpt show: /dev/disk0: Suspicious MBR at sector 0

gpt show: /dev/disk0: Pri GPT at sector 1

gpt show: /dev/disk0: Sec GPT at sector 490234751

start size index contents

0 1 MBR

1 1 Pri GPT header

2 32 Pri GPT table

34 6

40 409600 1 GPT part - C12A7328-F81F-11D2-BA4B-00A0C93EC93B

409640 255104784 2 GPT part - 48465300-0000-11AA-AA11-00306543ECAC

255514424 1269536 3 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC

256783960 96733608

353517568 136716288 4 GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7

490233856 863

490234719 32 Sec GPT table

490234751 1 Sec GPT header

Adams-MacBook-Pro:~ Adam$

Output of the command suggested:

Adams-MacBook-Pro:~ Adam$ sudo dd if=/dev/rdisk0s4 count=1 2>/dev/null | hexdump -C

00000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|

*

00000200

Thanks in advance.

MacBook Pro (Retina, 13-inch, Early 2013), OS X Yosemite (10.10.3), Windows 8.1

Posted on May 7, 2015 9:56 AM

Top-ranking reply

Loner T

Level 9

59,513 points

Posted on May 7, 2015 10:51 AM

Can you use Lost my Windows 7 Boot Camp partition after upgrading to Yosemite. Help! as a reference (you have the same issue) and download Testdisk and GPT Fdisk and get started with a Testdisk scan?

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54 replies

adamsouthern Author

Level 1

0 points

May 8, 2015 2:13 PM in response to Loner T

Loner T

Level 9

59,513 points

May 8, 2015 2:50 PM in response to adamsouthern

Are these from the same MS Data entry or two different ones? Can you show the top part where it shows MS Data and the three numbers?

adamsouthern Author

Level 1

0 points

May 8, 2015 2:51 PM in response to Loner T

These are both from the first MS Data I found. Just I had to scroll down.

Loner T

Level 9

59,513 points

May 8, 2015 2:59 PM in response to adamsouthern

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

Sudo gdisk /dev/rdisk0
P (print the full list of parts)
D (delete)
4 (part 4)
N (new part)
4 (part 4)
280403968 - Start offset in bytes (start point for Bootcamp part)
+209829881 - Size offset (as opposed to End offset)
0700 (Windows part type)
P (print list of all parts just to see what changes will be made)
W (Write the new GPT)
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.

Sudo gdisk /dev/disk0
P (Print list of parts)
R (Recover)
H (chooses Hybrid)
O (print current Hybrid MBR)
Partitions numbers to be hybridized: 2 3 4
Y (Good for GRUB question)
N (part 2 boot flag)
N (part 3 boot flag)
Y (part 4 boot flag make NTFS bootable partition)
O (print current Hybrid MBR)
W (Write the new MBR)
Y (Yes! write the new MBR)
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.

adamsouthern Author

Level 1

0 points

May 9, 2015 1:40 AM in response to Loner T

Well, it worked! All of those tests weren't great, but I haven't even been able to view the partition anywhere in finder/startup disk previously. Thank you so much!

Loner T

Level 9

59,513 points

May 9, 2015 5:59 AM in response to adamsouthern

I suggest a backup of OS X and Windows a baseline for future restores.

adamsouthern wrote:

Well, it worked! All of those tests weren't great, but I haven't even been able to view the partition anywhere in finder/startup disk previously. Thank you so much!

Which of the tests failed?

adamsouthern Author

Level 1

0 points

May 9, 2015 6:04 AM in response to Loner T

All of them, I don't know if this would've affected it, but I set the startup disk to Windows (via windows bootcamp panel) before losing the partition. But I've never been able to view my Windows files from finder.

Loner T

Level 9

59,513 points

May 9, 2015 6:28 AM in response to adamsouthern

Do you have any third-party NTFS software - Tuxera, Paragon, MacDrive or NTFS-3g or it's variants?

adamsouthern Author

Level 1

0 points

May 9, 2015 6:33 AM in response to Loner T

Nope, but I don't really mind not having it visible.

Loner T

Level 9

59,513 points

May 9, 2015 7:45 AM in response to adamsouthern

In Disk Utility can you click on the Bootcamp volume and post a screen shot similar to the following?

adamsouthern Author

Level 1

0 points

May 9, 2015 8:10 AM in response to Loner T

There's no option to verify it.

Nor can i mount it.

Loner T

Level 9

59,513 points

May 9, 2015 8:52 AM in response to adamsouthern

Can you click on Mount?

adamsouthern Author

Level 1

0 points

May 9, 2015 8:56 AM in response to Loner T

"BOOTCAMP cannot be mounted, please try running First Aid and try again" That's the thing though, it doesn't allow me to perform a repair.

Loner T

Level 9

59,513 points

May 9, 2015 9:09 AM in response to adamsouthern

Switch to Windows, and from an Administrative Command prompt, run chkdsk. Switch back to OS X and see if DU can mount it. OS X has a read-only NTFS driver, which is how the option to boot show up in System Preferences -> Startup Disk.

adamsouthern Author

Level 1

0 points

May 9, 2015 10:30 AM in response to Loner T

Sill giving me the error.

Bootcamp Broken after Resizing and OSX Update