Bootcamp partition has disappeared after upgrade to Yosemite 10.10

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Level 4

2,640 points

Bootcamp partition has disappeared after upgrade to Yosemite 10.10

Hello Loner T,

I've been following the threads of people with similar issues for the last couple of days now. I downloaded Testdisk and GPT disk both. And I've been trying to follow the directions as best I could on my own to see if I could re-set/re-write the GPT and MBR entries. My situation is a little different from the others in that I manually opened my iMac and installed an SSD which populates /dev/disk1(for recovery volume) and /disk2/ which is my boot drive. /dev/disk0 the internal 1TB drive became extra storage and location for the Bootcamp partition. So following these directions initially to pin down where on Disk0 things were located I narrowed it down to /dev/disk0s3

diskutil list
diskutil cs list (to find if Core Storage is the culprit)
Download GPT Disk from sourceforge.org and install it.
sudo gpt -vv -r show /dev/disk0
sudo fdisk /dev/disk0

Here's the output from each of the steps, the beginning of the tests----------------------------------------------------------

-------------------------------------------------------------------------------- -End of Tests-----------------------------------------------------

So /dev/disk0s3 is the location. But I'm having real difficulties now getting further as I tried this command just to see if I could find the 'R.NTFS' entry in the hexdump from the dd command:

sudo dd if=/dev/rdisk0s3 count=1 2>/dev/null | hexdump -C

Ambiguous output redirect

Do I have that commandline correct?

Also I've done a full run of Test disk in Quick Search and Deep Search that I can post if needed. I'm finding it's very odd compared to what I've seen other people posting so far. I've got 2 complete Windows partitions with what looks to be the same files in both locations. I did extend the volume at one point to boost it up to 250GB. Don't know if that's causing the GPT/MBR to show a total of 8 entries in Testdisk. But that's what I'm seeing when I run it. Will await any further steps or directions you might have. I'm hoping this is quick fix. But I'm willing to do a full GPT re-wrtie/reset and an MBR rebuild if necessary and of course the Windows Recovery if it comes to that. I cannot thank you enough for being so generous with your knowledge and expertise, it's been a real education in the low level vagaries of disk management on the Mac for the past 2-3 days.

OS X Yosemite (10.10)

Posted on Nov 15, 2014 6:22 AM

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Answer 1

Loner T

Level 9

59,513 points

Nov 16, 2014 10:35 AM in response to elikness

Your are correct, it should be GPT#3, not GPT#4.

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Answer 2

elikness Author

Level 4

2,640 points

Nov 16, 2014 11:56 AM in response to Loner T

So I will use these values for start/end/size when I recreate the GPT for /dev/disk0 GPT#3

start end size

1465253888

1953523704

488269817

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Answer 3

elikness Author

Level 4

2,640 points

Nov 16, 2014 12:19 PM in response to Loner T

🙂SUCCESS~!
Bootcamp has reappeared. And this is what I'm getting off of fdisk and dd-with the hexdump

Note: 'R.NTFS' appears exactly where it should be appear when I run the dd command as outlined in your directions. It appears in the Bootcamp control panel, on the desktop and I'm going out now to see if it appears as a bootable device holding down the option key on restart. As far as I'm concerned your method is the best step-by-step for doing this manually. I think if Apple creates a fix for this it should be python or shell-based script of some sort that figures out where the offsets are and where the R.NTFS is located.

Disk: /dev/disk0 geometry: 121601/255/63 [1953525168 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: AF 25 127 15 - 1023 254 63 [ 409640 - 1464843744] HFS+

*3: 07 1023 254 63 - 1023 254 63 [1465253888 - 488269817] HPFS/QNX/AUX

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

2-iMac:~ ericlikness$ sudo dd if=/dev/rdisk0s3 count=1 2>/dev/null | hexdump -C

00000000 eb 52 90 4e 54 46 53 20 20 20 20 00 02 08 00 00 |.R.NTFS .....|

00000010 00 00 00 00 00 f8 00 00 3f 00 ff 00 00 00 56 57 |........?.....VW|

00000020 00 00 00 00 80 00 80 00 ff 57 0c 1d 00 00 00 00 |.........W......|

00000030 4a 07 00 00 00 00 00 00 49 07 00 00 00 00 00 00 |J.......I.......|

00000040 f6 00 00 00 01 00 00 00 50 66 ff 0d f3 c9 cd 01 |........Pf......|

00000050 00 00 00 00 fa 33 c0 8e d0 bc 00 7c fb 68 c0 07 |.....3.....|.h..|

00000060 1f 1e 68 66 00 cb 88 16 0e 00 66 81 3e 03 00 4e |..hf......f.>..N|

00000070 54 46 53 75 15 b4 41 bb aa 55 cd 13 72 0c 81 fb |TFSu..A..U..r...|

00000080 55 aa 75 06 f7 c1 01 00 75 03 e9 dd 00 1e 83 ec |U.u.....u.......|

00000090 18 68 1a 00 b4 48 8a 16 0e 00 8b f4 16 1f cd 13 |.h...H..........|

000000a0 9f 83 c4 18 9e 58 1f 72 e1 3b 06 0b 00 75 db a3 |.....X.r.;...u..|

000000b0 0f 00 c1 2e 0f 00 04 1e 5a 33 db b9 00 20 2b c8 |........Z3... +.|

000000c0 66 ff 06 11 00 03 16 0f 00 8e c2 ff 06 16 00 e8 |f...............|

000000d0 4b 00 2b c8 77 ef b8 00 bb cd 1a 66 23 c0 75 2d |K.+.w......f#.u-|

000000e0 66 81 fb 54 43 50 41 75 24 81 f9 02 01 72 1e 16 |f..TCPAu$....r..|

000000f0 68 07 bb 16 68 52 11 16 68 09 00 66 53 66 53 66 |h...hR..h..fSfSf|

00000100 55 16 16 16 68 b8 01 66 61 0e 07 cd 1a 33 c0 bf |U...h..fa....3..|

00000110 0a 13 b9 f6 0c fc f3 aa e9 fe 01 90 90 66 60 1e |.............f`.|

00000120 06 66 a1 11 00 66 03 06 1c 00 1e 66 68 00 00 00 |.f...f.....fh...|

00000130 00 66 50 06 53 68 01 00 68 10 00 b4 42 8a 16 0e |.fP.Sh..h...B...|

00000140 00 16 1f 8b f4 cd 13 66 59 5b 5a 66 59 66 59 1f |.......fY[ZfYfY.|

00000150 0f 82 16 00 66 ff 06 11 00 03 16 0f 00 8e c2 ff |....f...........|

00000160 0e 16 00 75 bc 07 1f 66 61 c3 a1 f6 01 e8 09 00 |...u...fa.......|

00000170 a1 fa 01 e8 03 00 f4 eb fd 8b f0 ac 3c 00 74 09 |............<.t.|

00000180 b4 0e bb 07 00 cd 10 eb f2 c3 0d 0a 41 20 64 69 |............A di|

00000190 73 6b 20 72 65 61 64 20 65 72 72 6f 72 20 6f 63 |sk read error oc|

000001a0 63 75 72 72 65 64 00 0d 0a 42 4f 4f 54 4d 47 52 |curred...BOOTMGR|

000001b0 20 69 73 20 63 6f 6d 70 72 65 73 73 65 64 00 0d | is compressed..|

000001c0 0a 50 72 65 73 73 20 43 74 72 6c 2b 41 6c 74 2b |.Press Ctrl+Alt+|

000001d0 44 65 6c 20 74 6f 20 72 65 73 74 61 72 74 0d 0a |Del to restart..|

000001e0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|

000001f0 00 00 00 00 00 00 8a 01 a7 01 bf 01 00 00 55 aa |..............U.|

00000200

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Answer 4

elikness Author

Level 4

2,640 points

Nov 16, 2014 12:47 PM in response to Loner T

GPT was re-written AND rebooted. Bootcamp appeared on the desktop and in the Bootcamp control panel, didn't show up while holding down Option during the first reboot. Rebuilt the MBR and set boot flag on the Bootcamp part, and re-wrote MBR and rebooted. I let it boot all the way to the Mac OS desktop for safety and rebooted 1 more time, this time while holding down Option key and Windows part showed up as a bootable volume. I selected it just out of curiosity expecting I might have to get a Recovery disk burned off my Win8.1update1 .iso. Guess what?! Windows 8.1 booted all the way to the desktop without a single warning message or glitch. In fact, even more reassuring was I had applied a software update on shutdown, and the lag starting up I noticed was the software update completing. It's as if nothing has gone wrong or changed. I'm fully back to normal thanks to you Loner T. Thanks for your time and patience and for your detail instructions. I'm copy/pasting the notes I compiled for Testdisk and GPT disk here if you want to use it as a boilerplate template. This method seems to work even for oddball setups like the one I have (where /dev/disk0 is not the boot disk).

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

https://discussions.apple.com/thread/6643460

Download GPT disk from Sourceforge.org and Testdisk from www.cgsecurity.org
Open Terminal from the Utilities folder and copy/paste and run these commands
diskutil list
diskutil cs list (to find if Core Storage is the culprit)
sudo gpt -vv -r show /dev/disk0
sudo fdisk /dev/disk0

All these commands will give you a sense if the GPT listing matches MBR. If it matches it's a quick fix. But first look for the NTFS header in the partition you have identified in the previous steps.

Sudo dd if=/dev/rdisk0s4 count=1 2>/dev/null | hexdump -C
Look for the string, "R.NTFS" if that exists then do the next step:
Sudo fdisk -e /dev/disk0 (edits the exist MBR)
Setpid 4 (edit part 4)
07 (partition type in hex)
Flag 4 (make it bootable)
P (print the new table to the terminal)
W (write in memory copy of the new table)
Y (yes please write it!)
Reboot! Look for bootcamp on Option-Startup, Startup disks and the desktop
Look for files in Bootcamp if it appears on the desktop.

If that doesn't work download/run Testdisk (www.cgsecurity.org)

Run Testdisk and look at the contents of the partition it finds with a QuickSearch using EFI/GTP type partition.
If you see files in that partition, specifically "System Volume Information" you're nearly set, just need to rebuild the MBR for that partition.
If you don't see files you need to perform the more extensive DeepSearch. Once it finds ALL the partitions, print files in each until you find the "System Volume Information" section. Once you discover that one, get the start/end offsets and the filesize to use for the GPT rebuild steps using GPT disk.

Rebuild using start/end offsets from Testdisk DeepSearch using GPT disk

Sudo gdisk /dev/rdisk0
P (print the full list of parts)
D (delete)
4 (part 4)
N (new part)
4 (part 4)
Start offset in bytes (start point for Bootcamp part)
+(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

Sudo gdisk /dev/disk0
P (Print list of parts)
R (Recover)
H (chooses Hybrid)
Partitions numbers to be hybridized: 2 3 4
Y (boot flag 1)
N (part 2 flag)
N (part 3 flag)
Y (part 4 flag make bootable partition)
W (Write the new MBR)
Y (Yes! write the new MBR)
Reboot

Check all partitions with fdisk on reboot.

sudo fdisk /dev/disk0 (everything should match and Bootcamp should be visible everywhere)

You may need to use Windows Recovery to fix the windows partition once booted into Bootcamp. Keep a boot disk handy. May also require fixing the bootfiles with EasyBCD, so have that on hand as well to finish up recovery in the Windows partition.

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Answer 5

Loner T

Level 9

59,513 points

Nov 16, 2014 12:50 PM in response to elikness

Thank you for documenting your notes. I can use it as a reference for others who may be in a situation similar to your.

Glad to see it all work.

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Answer 6

Texmurph

Level 1

0 points

Nov 17, 2014 8:57 PM in response to Loner T

What a complete crock of crap!!! I was going to upgrade to Yosemite on my bootcamped MacBook air... and then I saw the computer memory dumps that you guys have been exchanging just to hopefully get maybe one person back to a working bootcamp system. Upgrade an operating system in one partition and screw up the operating system in another partition? Can Apple be serious? There should be an APB from Apple on this. A WARNING sign at the front of every Apple store. I shouldn't be hearing about this from the poor geniuses in the trenches helping to patch each other up with bandages. Do they know how many people they are going to screw over with this? Forget Yosemite. Wake me when this nightmare is over.

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Answer 7

Loner T

Level 9

59,513 points

Nov 18, 2014 3:23 AM in response to Texmurph

Texmurph wrote:

Forget Yosemite. Wake me when this nightmare is over.

It has been frustrating, to say the least. If you do need Yosemite features, I would suggest using third-party tools to backup your Windows OS and Data (twice over, if you can), wipe it off the Mac, Upgrade, and Restore Windows/BC.

There is enough information on the ASC discussions for the BC Engineers to fix it in the next patch release of Yosemite.

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Answer 8

Csound1

Level 9

60,033 points

Nov 18, 2014 3:31 AM in response to Texmurph

Texmurph wrote:

What a complete crock of crap!!! I was going to upgrade to Yosemite on my bootcamped MacBook air... and then I saw the computer memory dumps that you guys have been exchanging just to hopefully get maybe one person back to a working bootcamp system. Upgrade an operating system in one partition and screw up the operating system in another partition? Can Apple be serious? There should be an APB from Apple on this. A WARNING sign at the front of every Apple store. I shouldn't be hearing about this from the poor geniuses in the trenches helping to patch each other up with bandages. Do they know how many people they are going to screw over with this? Forget Yosemite. Wake me when this nightmare is over.

This is not a new issue, it existed long before Yosemite (search this site). It is a symptom of the ill fit between the two operating system requirements.

Re-Partitioning a drive that has an installation on it without making a backup first is a bad choice.

Windows installations are much more reliable on Windows machines.

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Answer 9

Loner T

Level 9

59,513 points

Nov 18, 2014 6:39 AM in response to Csound1

Csound1 wrote:

This is not a new issue, it existed long before Yosemite (search this site). It is a symptom of the ill fit between the two operating system requirements.

Apple should document it and provide appropriate caveats to consumers. They should also try to fix problems instead of letting them linger across multiple versions and version releases.

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Answer 10

Csound1

Level 9

60,033 points

Nov 18, 2014 6:43 AM in response to Loner T

Then you should tell them, Apple.com/feedback

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Answer 11

Texmurph

Level 1

0 points

Nov 18, 2014 6:45 AM in response to Csound1

Sounds like you are advocating that I should buy a Windows machine to sit beside my MacBook Pro in my home office, and another windows machine to carry on the road with me along with my MacBook Air. Brilliant. Why didn't I think of that? The thousands of dollars in expense? I'm rich. The extra bulk of a second machine and adapter on the road? I can cram it in and carry it, no problem.

I have been running OSX & Windows 7 using bootcamp on each of my machines for years. Both work perfectly.

In no way, shape, or form should the upgrade to Yosemite on the Mac side of a bootcamped laptop break Windows 7 on the PC side. Of course you need to back up both operating systems first, and there is no re-partitioning involved unless you count the improper repartitioning that the Yosemite install appears to do.

I love Macs & OSX. I love PCs and Windows. There are thousands out there like me with legitimate reasons to run both operating systems on the same machine for both personal and business use. We must all learn to live with that.

Apple should not have released Yosemite with this serious problem, and they should fix it pronto.

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Answer 12

Loner T

Level 9

59,513 points

Nov 18, 2014 6:51 AM in response to Csound1

Csound1 wrote:

Then you should tell them, Apple.com/feedback

I have provided feedback and bug reports since the dawn of Mavericks. I did the same with Yosemite DP1-6. Is data loss Apple's favorite game? I am certain you are not trying to defend Apple, are you?

From http://images.apple.com/legal/sla/docs/OSX1010.pdf

TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW, THE APPLE SOFTWARE AND SERVICES ARE PROVIDED “AS IS” AND “AS AVAILABLE”, WITH ALL FAULTS AND WITHOUT WARRANTY OF ANY KIND, AND APPLE AND APPLE'S LICENSORS (COLLECTIVELY REFERRED TO AS “APPLE” FOR THE PURPOSES OF SECTIONS 7 AND 8) HEREBY DISCLAIM ALL WARRANTIES AND CONDITIONS WITH RESPECT TO THE APPLE SOFTWARE AND SERVICES, EITHER EXPRESS, IMPLIED OR STATUTORY, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES AND/OR CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY, FITNESS FOR A PARTICULAR PURPOSE, ACCURACY, QUIET ENJOYMENT, AND NON-INFRINGEMENT OF THIRD PARTY RIGHTS.

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Answer 13

BroFlav

Level 1

29 points

Nov 18, 2014 6:51 AM in response to Csound1

It is a symptom of the ill fit between the two operating system requirements.

Re-Partitioning a drive that has an installation on it without making a backup first is a bad choice.

Windows installations are much more reliable on Windows machines.

I think these problems stem from the EFI version Apple uses on their system. I have read that Apple still uses a sort of BIOS system to make a Bootcamp partition bootable. There is no need to use an MBR partition with the newer Windows versions (7 and 8). They can boot in EFI systems using GPT partitions just fine. For some reason, though, Apple is still using MBR types of partitions for Bootcamp. I'm not sure what is the reason behind this technological choice.

The fact that Apple did not update their HFS+ filesystem also doesn't help. There are better filesystems already, many of which are not proprietary, so there would be no problem with the license.

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Answer 14

Loner T

Level 9

59,513 points

Nov 18, 2014 7:01 AM in response to BroFlav

Intel has two separate EFI specifications preUEFI and EFI 1.1 (used by Apple) do not mix well. Windows 7 has partial support for EFI, but W8.1 seems to be the first 'full' UEFI. MBR provided a route to support many different Windows implementations before the UEFI specification was fully incorporated into OSes. Newer Mac machines do support UEFI (post-2013 machines).

I run Windows via UEFI on a late 2013 rMBP. On a 2012 MBP, UEFI does not work. One potential solution I have suggested in my feedback and bug reports is to provide EFI updates for machines which are capable of running Yosemite to become UEFI-compliant so W8+ (and W10) can run native UEFI. I am uncertain if Apple has the motivation/resources to make such changes available to consumers.

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Answer 15

Csound1

Level 9

60,033 points

Nov 18, 2014 7:16 AM in response to Texmurph

Texmurph wrote:

Sounds like you are advocating that I should buy a Windows machine to sit beside my MacBook Pro in my home office, and another windows machine to carry on the road with me along with my MacBook Air.

You are easily misled then

Good luck (see what you can read into that)

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