Windows partition missing from bootcamp.

Question

Windows partition missing from bootcamp.

I haven't been on my Windows partition in a couple of weeks and when I went to login to it today through the startup screen it was not visible. I can't think of anything that I've done that would cause a major change in the system and partitions. In the disk utility it now appears as 'disk0s4' and is unrepairable and I can't access the files through Finder.

Is this partition recoverable and, if so, how do I go about doing so? Please help. Thanks in advance.

MacBook Pro (15-inch Mid 2012), OS X Yosemite (10.10.4)

Posted on Jul 18, 2015 5:10 PM

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Answer 1

Loner T

Level 9

59,536 points

Jul 18, 2015 5:28 PM in response to citiesandeyes4

Can you post the output of the following Terminal commands?

diskutil list

diskutil cs list

sudo gpt -vv -r show /dev/disk0

sudo fdisk /dev/disk0

The "sudo" commands will prompt for your password, and it will not be echoed back. You may also see a warning about improper use of "sudo" and potential data loss due to "abuse" of the command.

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Answer 2

Jul 18, 2015 5:48 PM in response to Loner T

Hi Loner T, thanks for taking this up.

diskutil list:

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *750.2 GB disk0

1: EFI EFI 209.7 MB disk0s1

2: Apple_HFS Macintosh HD 522.1 GB disk0s2

3: Apple_Boot Recovery HD 650.0 MB disk0s3

4: Microsoft Basic Data 128.0 GB disk0s4

diskutil cs list

No CoreStorage logical volume groups found

sudo gpt -vv - show /dev/disk0

gpt show: /dev/disk0: mediasize=750156374016; sectorsize=512; blocks=1465149168

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 1465149167

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 1019700872 2 GPT part - 48465300-0000-11AA-AA11-00306543ECAC

1020110512 1269536 3 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC

1021380048 193770032

1215150080 249997312 4 GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7

1465147392 1743

1465149135 32 Sec GPT table

1465149167 1 Sec GPT header

sudo fdisk /dev/disk0

Disk: /dev/disk0

geometry: 91201/255/63 [1465149168 sectors]

Signature: 0xAA55

Starting Ending

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

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

1: EE 1023 254 63 - 1023 254 63 [ 1 - 409639] <Unknown ID>

2: AF 1023 254 63 - 1023 254 63 [ 409640 - 1019700872] HFS+

3: AB 1023 254 63 - 1023 254 63 [1020110512 - 1269536] Darwin Boot

4: 0C 1023 254 63 - 1023 254 63 [1215150080 - 249997312] Win95 FAT32L

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Answer 3

Loner T

Level 9

59,536 points

Jul 18, 2015 5:56 PM in response to citiesandeyes4

You seem to have a very prevalent malady of the upgrade. There is another user with a similar issue. Please see Lost my Windows 7 Boot Camp partition after upgrading to Yosemite. Help! as a reference and download Testdisk and GPT Fdisk and start a Testdisk scan. The gap between GPT3 and GPT4 is the most likely place for a lost NTFS header.

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Answer 4

Aug 24, 2015 1:43 AM in response to Loner T

Hi Loner T,

I thought everything was going great and my situation was very similar to the other post you mentioned. However, when I ran the steps with what I thought was the right information, Boot Camp never appeared in Finder or in the System Preferences -> Startup Disk. However, when I boot up into the Statup Manager, there is once again an icon for a Windows drive. When I click on it though it, it's just a black screen that says Missing Operating System. Any idea on how to fix this?

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Answer 5

Aug 24, 2015 1:52 AM in response to citiesandeyes4

This is the new info for the first question you asked.

diskutil list

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *750.2 GB disk0

1: EFI EFI 209.7 MB disk0s1

2: Apple_HFS Macintosh HD 522.1 GB disk0s2

3: Apple_Boot Recovery HD 650.0 MB disk0s3

4: Microsoft Basic Data 227.2 GB disk0s4

diskutil cs list

No CoreStorage logical volume groups found

sudo gpt -vv -r show /dev/disk0

gpt show: /dev/disk0: mediasize=750156374016; sectorsize=512; blocks=1465149168

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 1465149167

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 1019700872 2 GPT part - 48465300-0000-11AA-AA11-00306543ECAC

1020110512 1269536 3 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC

1021380048 443766777 4 GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7

1465146825 2310

1465149135 32 Sec GPT table

1465149167 1 Sec GPT header

sudo fdisk /dev/disk0

Disk: /dev/disk0 geometry: 91201/255/63 [1465149168 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 - 1019700872] HFS+

3: AB 1023 254 63 - 1023 254 63 [1020110512 - 1269536] Darwin Boot

*4: 07 1023 254 63 - 1023 254 63 [1021380048 - 443766777] HPFS/QNX/AUX

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Answer 6

Loner T

Level 9

59,536 points

Aug 24, 2015 3:03 PM in response to citiesandeyes4

Do you have some of the Testdisk screens that you can share, so I can check them?

Can you post the output of the following command?

sudo dd if=/dev/rdisk0s4 count=1 2>/dev/null | hexdump -C

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Answer 7

Aug 24, 2015 10:08 PM in response to Loner T

The output for that command is:

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

*

00000200

I'll run Testdisk again to get some screens.

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Answer 8

Loner T

Level 9

59,536 points

Aug 25, 2015 8:56 AM in response to citiesandeyes4

Do you have Testdisk screens before you did the following?

However, when I ran the steps with what I thought was the right information,

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Answer 9

Aug 28, 2015 9:57 PM in response to Loner T

Unfortunately, no. Lost them when I rebooted.

When I run Testdisk again this screen pops up which is definitely new.

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Answer 10

Loner T

Level 9

59,536 points

Aug 30, 2015 11:20 AM in response to citiesandeyes4

Please continue withe Quick Search.

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Answer 11

Aug 30, 2015 11:48 AM in response to Loner T

The first and third MS Data return, "Can't open filesystem. Filesystem seems damaged."

I'll start a deeper search now but it'll probably take a day or two if it's anything like the last time I tried.

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Answer 12

Loner T

Level 9

59,536 points

Aug 30, 2015 12:01 PM in response to citiesandeyes4

No. You do not need a deeper search.

GPT 3 Start	GPT 3 Size	GPT 3 End	NTFS Start	Sector Offset	NTFS Size	NTFS End	Sector Offset (MB)	NTFS(Gb)
1020110512	1269536	1021380048	1021380608	560	443766777	1465147384	0	211.60

Does the NTFS size look correct?

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Answer 13

Aug 30, 2015 12:23 PM in response to Loner T

I believe so.

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Answer 14

Loner T

Level 9

59,536 points

Aug 30, 2015 12:37 PM in response to citiesandeyes4

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 theaction being taken. Gdisk has one-character commands except when entering numbers. Please read the Sample Q&A at the end of this post.

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)
1021380608 ( - Start offset in sectors or the start point for Bootcamp part)
+443766777 ( - 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. 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.

Sudo gdisk /dev/rdisk0
P (Print list of parts)
R (Recover)
O (print current Hybrid MBR)
H (chooses Hybrid)
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.

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Answer 15

Aug 30, 2015 1:14 PM in response to Loner T

I'm thrilled to be writing this response in Windows. Thank you so much for your help. Can I send you some money for your time?

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