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Bootcamp Partition Lost After Yosemite Upgrade

Like many others, I upgraded to Yosemite and have now lost access to Bootcamp and my Windows partition (which has been replaced with a greyed out disk0s4). It seems LonerT has brilliantly found a solution for this, but I am struggling to follow the sequence of steps delineated in various threads on this topic. I have/had a lot of mission critical data on my Windows partition, so am worried about accidentally making the situation worse. 😕


Here is the information I cobbled together so far:


diskutil list

/dev/disk0

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *500.3 GB disk0

1: EFI EFI 209.7 MB disk0s1

2: Apple_CoreStorage 350.2 GB disk0s2

3: Apple_Boot Recovery HD 650.1 MB disk0s3

4: Microsoft Basic Data 90.0 GB disk0s4

/dev/disk1

#: TYPE NAME SIZE IDENTIFIER

0: Apple_HFS Macintosh HD *349.8 GB disk1

Logical Volume on disk0s2

85806C0D-965A-4E1F-B73B-54084FBB7FDF

Unlocked Encrypted


diskutil cs list

CoreStorage logical volume groups (1 found)

|

+-- Logical Volume Group 9F66D719-DEBC-482D-9725-A2D0EFC1B49D

=========================================================

Name: Macintosh HD

Status: Online

Size: 350191783936 B (350.2 GB)

Free Space: 954368 B (954.4 KB)

|

+-< Physical Volume 35A6BD2F-48F0-4A12-924D-774C86B9C09D

| ----------------------------------------------------

| Index: 0

| Disk: disk0s2

| Status: Online

| Size: 350191783936 B (350.2 GB)

|

+-> Logical Volume Family F9D06192-F7A3-48CD-B25A-D5DD629EFB17

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

Encryption Status: Unlocked

Encryption Type: AES-XTS

Conversion Status: Complete

Conversion Direction: -none-

Has Encrypted Extents: Yes

Fully Secure: Yes

Passphrase Required: Yes

|

+-> Logical Volume 85806C0D-965A-4E1F-B73B-54084FBB7FDF

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

Disk: disk1

Status: Online

Size (Total): 349838393344 B (349.8 GB)

Conversion Progress: -none-

Revertible: Yes (unlock and decryption required)

LV Name: Macintosh HD

Volume Name: Macintosh HD

Content Hint: Apple_HFS


sudo gpt -vv -r show /dev/disk0

Password:

gpt show: /dev/disk0: mediasize=500277790720; sectorsize=512; blocks=977105060

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 977105059

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 683968328 2 GPT part - 53746F72-6167-11AA-AA11-00306543ECAC

684377968 1269760 3 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC

685647728 115677328

801325056 175779840 4 GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7

977104896 131

977105027 32 Sec GPT table

977105059 1 Sec GPT header


sudo fdisk /dev/disk0

Disk: /dev/disk0 geometry: 60821/255/63 [977105060 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: AC 1023 254 63 - 1023 254 63 [ 409640 - 683968328] <Unknown ID>

3: AB 1023 254 63 - 1023 254 63 [ 684377968 - 1269760] Darwin Boot

4: 0C 1023 254 63 - 1023 254 63 [ 801325056 - 175779840] Win95 FAT32L


sudo dd if=/dev/rdisk0s4 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 40 c3 2f |........?....@./|

00000020 00 00 00 00 80 00 80 00 ff 2f 7a 0a 00 00 00 00 |........./z.....|

00000030 00 00 0c 00 00 00 00 00 02 00 00 00 00 00 00 00 |................|

00000040 f6 00 00 00 01 00 00 00 9f b7 f0 7c ec f0 7c 26 |...........|..|&|

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 70 0e 16 68 09 00 66 53 66 53 66 |h...hp..h..fSfSf|

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

00000110 28 10 b9 d8 0f fc f3 aa e9 5f 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 a0 f8 01 e8 09 00 |...u...fa.......|

00000170 a0 fb 01 e8 03 00 f4 eb fd b4 01 8b f0 ac 3c 00 |..............<.|

00000180 74 09 b4 0e bb 07 00 cd 10 eb f2 c3 0d 0a 41 20 |t.............A |

00000190 64 69 73 6b 20 72 65 61 64 20 65 72 72 6f 72 20 |disk read error |

000001a0 6f 63 63 75 72 72 65 64 00 0d 0a 42 4f 4f 54 4d |occurred...BOOTM|

000001b0 47 52 20 69 73 20 6d 69 73 73 69 6e 67 00 0d 0a |GR is missing...|

000001c0 42 4f 4f 54 4d 47 52 20 69 73 20 63 6f 6d 70 72 |BOOTMGR is compr|

000001d0 65 73 73 65 64 00 0d 0a 50 72 65 73 73 20 43 74 |essed...Press Ct|

000001e0 72 6c 2b 41 6c 74 2b 44 65 6c 20 74 6f 20 72 65 |rl+Alt+Del to re|

000001f0 73 74 61 72 74 0d 0a 00 8c a9 be d6 00 00 55 aa |start.........U.|

00000200


TestDisk 7.0, Data Recovery Utility, April 2015

Christophe GRENIER <grenier@cgsecurity.org>

http://www.cgsecurity.org



TestDisk is free software, and

comes with ABSOLUTELY NO WARRANTY.


Select a media (use Arrow keys, then press Enter):

>Disk /dev/disk0 - 500 GB / 465 GiB (RO)

Disk /dev/rdisk0 - 500 GB / 465 GiB (RO)

Disk /dev/rdisk1 - 349 GB / 325 GiB



TestDisk 7.0, Data Recovery Utility, April 2015

Christophe GRENIER <grenier@cgsecurity.org>

http://www.cgsecurity.org



Disk /dev/rdisk1 - 349 GB / 325 GiB


Please select the partition table type, press Enter when done.

[Intel ] Intel/PC partition

[EFI GPT] EFI GPT partition map (Mac i386, some x86_64...)

[Humax ] Humax partition table

[Mac ] Apple partition map

>[None ] Non partitioned media

[Sun ] Sun Solaris partition

[XBox ] XBox partition

[Return ] Return to disk selection




Hint: None partition table type has been detected.

Note: Do NOT select 'None' for media with only a single partition. It's very

rare for a disk to be 'Non-partitioned'.


TestDisk 7.0, Data Recovery Utility, April 2015

Christophe GRENIER <grenier@cgsecurity.org>

http://www.cgsecurity.org


Disk /dev/disk0 - 500 GB / 465 GiB - 977105060 sectors (RO)

Current partition structure:

Partition Start End Size in sectors


1 P EFI System 40 409639 409600 [EFI System Partitio

2 P Unknown 409640 684377967 683968328 [Macintosh HD]

3 P Mac Boot 684377968 685647727 1269760 [Recovery HD]

Warning: number of heads/cylinder mismatches 255 (NTFS) != 1 (HD)

Warning: number of sectors per track mismatches 63 (NTFS) != 1 (HD)

4 P MS Data 801325056 977104895 175779840 [BOOTCAMP]




So two questions: Which of these media should I select and what is the correct partition type? Where do I find the start offset and size offset values you reference here:


Rebuild using start/end offsets from Testdisk DeepSearch using GPT Fdisk (http://sourceforge.net/projects/gptfdisk/)

  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. 49741824 - Start offset in bytes (start point for Bootcamp part)
  8. +187234297(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.

Thank you!!


Message was edited by: bjn1001

MacBook Pro (Retina, 15-inch, Late 2013), OS X Yosemite (10.10.3), null

Posted on Aug 8, 2015 4:59 AM

Reply
20 replies

Aug 8, 2015 7:15 AM in response to Loner T

Thank you for the quick response LonerT! I am running this now, although I am a bit like the monkey learning sign language...I can mimic the hand gestures (key strokes) but not sure I understand the meaning behind them 😊


TestDisk 7.0, Data Recovery Utility, April 2015

Christophe GRENIER <grenier@cgsecurity.org>

http://www.cgsecurity.org


Disk /dev/disk0 - 500 GB / 465 GiB - 977105060 sectors (RO)


The harddisk (500 GB / 465 GiB) seems too small! (< 500 GB / 466 GiB)

Check the harddisk size: HD jumpers settings, BIOS detection...


The following partition can't be recovered:

Partition Start End Size in sectors

> Mac HFS 977105020 978374555 1269536



TestDisk 7.0, Data Recovery Utility, April 2015

Christophe GRENIER <grenier@cgsecurity.org>

http://www.cgsecurity.org


Disk /dev/disk0 - 500 GB / 465 GiB - 977105060 sectors (RO)

Partition Start End Size in sectors

>P EFI System 40 409639 409600 [EFI]

D MS Data 625545217 801325056 175779840

D Mac HFS 684377964 685647499 1269536

D Mac HFS 685647724 686917483 1269760

D MS Data 801325056 977104895 175779840

D Mac HFS 975835488 977105023 1269536







Structure: Ok. Use Up/Down Arrow keys to select partition.

Use Left/Right Arrow keys to CHANGE partition characteristics:

P=Primary D=Deleted

Keys A: add partition, L: load backup, T: change type, P: list files,

Enter: to continue

FAT32, blocksize=512, 209 MB / 200 MiB


TestDisk 7.0, Data Recovery Utility, April 2015

Christophe GRENIER <grenier@cgsecurity.org>

http://www.cgsecurity.org





TestDisk 7.0, Data Recovery Utility, April 2015

Christophe GRENIER <grenier@cgsecurity.org>

http://www.cgsecurity.org


Disk /dev/rdisk0 - 500 GB / 465 GiB - 977105060 sectors (RO)

Current partition structure:

Partition Start End Size in sectors


1 P EFI System 40 409639 409600 [EFI System Partitio

2 P Unknown 409640 684377967 683968328 [Macintosh HD]

3 P Mac Boot 684377968 685647727 1269760 [Recovery HD]

Warning: number of heads/cylinder mismatches 255 (NTFS) != 1 (HD)

Warning: number of sectors per track mismatches 63 (NTFS) != 1 (HD)

4 P MS Data 801325056 977104895 175779840 [BOOTCAMP]

Aug 8, 2015 11:41 AM in response to Loner T

Thank you...it is still analyzing but less than half way through. Do I need to complete the quick search to perform the step you mentioned above?


TestDisk 7.0, Data Recovery Utility, April 2015

Christophe GRENIER <grenier@cgsecurity.org>

http://www.cgsecurity.org


Disk /dev/rdisk0 - 500 GB / 465 GiB - 977105060 sectors (RO)

Analyse sector 373293056/977105059: 00%



check_FAT: Unusual media descriptor (0xf0!=0xf8)

Warning: number of heads/cylinder mismatches 16 (FAT) != 1 (HD)

Warning: number of sectors per track mismatches 32 (FAT) != 1 (HD)


EFI System 40 409639 409600 [EFI]

Aug 8, 2015 4:20 PM in response to Loner T

Hi LonerT,


The analyzer finally completed and I selected the partition you mentioned and hit "p" to list files but got a "Can't open filesystem. Filesystem seems damaged." message. I have reselected that partition and selected "deeper search," which is now running. Do you generally have to run deeper search prior to listing files with the P command? Thanks again.



TestDisk 7.0, Data Recovery Utility, April 2015

Christophe GRENIER <grenier@cgsecurity.org>

http://www.cgsecurity.org


Disk /dev/rdisk0 - 500 GB / 465 GiB - 977105060 sectors (RO)


The harddisk (500 GB / 465 GiB) seems too small! (< 500 GB / 466 GiB)

Check the harddisk size: HD jumpers settings, BIOS detection...


The following partition can't be recovered:

Partition Start End Size in sectors

> Mac HFS 977105020 978374555 1269536











[ Continue ]

HFS+ blocksize=4096, 650 MB / 619 MiB



TestDisk 7.0, Data Recovery Utility, April 2015

Christophe GRENIER <grenier@cgsecurity.org>

http://www.cgsecurity.org


Disk /dev/rdisk0 - 500 GB / 465 GiB - 977105060 sectors (RO)

Partition Start End Size in sectors

>P EFI System 40 409639 409600 [EFI]

D MS Data 625545217 801325056 175779840

D Mac HFS 684377964 685647499 1269536

D Mac HFS 685647724 686917483 1269760

D MS Data 801325056 977104895 175779840

D Mac HFS 975835488 977105023 1269536







Structure: Ok. Use Up/Down Arrow keys to select partition.

Use Left/Right Arrow keys to CHANGE partition characteristics:

P=Primary D=Deleted

Keys A: add partition, L: load backup, T: change type, P: list files,

Enter: to continue

FAT32, blocksize=512, 209 MB / 200 MiB


TestDisk 7.0, Data Recovery Utility, April 2015

Christophe GRENIER <grenier@cgsecurity.org>

http://www.cgsecurity.org


MS Data 801325056 977104895 175779840




Can't open filesystem. Filesystem seems damaged.














>[ Quit ]


TestDisk 7.0, Data Recovery Utility, April 2015

Christophe GRENIER <grenier@cgsecurity.org>

http://www.cgsecurity.org


Disk /dev/rdisk0 - 500 GB / 465 GiB - 977105060 sectors (RO)

Analyse sector 557056/977105059: 00%



check_FAT: Unusual media descriptor (0xf0!=0xf8)

Warning: number of heads/cylinder mismatches 16 (FAT) != 1 (HD)

Warning: number of sectors per track mismatches 32 (FAT) != 1 (HD)


EFI System 40 409639 409600 [EFI]

check_FAT: Unusual media descriptor (0xf0!=0xf8)

Warning: number of heads/cylinder mismatches 16 (FAT) != 1 (HD)

Warning: number of sectors per track mismatches 32 (FAT) != 1 (HD)


EFI System 46 409645 409600 [EFI]







Stop

Aug 9, 2015 5:27 PM in response to Loner T

Hi LonerT,


I ran the deeper search, which yielded the below.


TestDisk 7.0, Data Recovery Utility, April 2015

Christophe GRENIER <grenier@cgsecurity.org>

http://www.cgsecurity.org


Disk /dev/rdisk0 - 500 GB / 465 GiB - 977105060 sectors (RO)


The harddisk (500 GB / 465 GiB) seems too small! (< 649 GB / 604 GiB)

Check the harddisk size: HD jumpers settings, BIOS detection...


The following partitions can't be recovered:

Partition Start End Size in sectors

> MS Data 817546816 993326655 175779840

MS Data 977104888 1268561904 291457017

MS Data 977104895 1152884734 175779840

Mac HFS 977105020 978374555 1269536








[ Continue ]


I selected the above partition and tried to list files for the row below, but unfortunately received the same "can't open file system" error message. Any suggestions? Thanks again.


TestDisk 7.0, Data Recovery Utility, April 2015

Christophe GRENIER <grenier@cgsecurity.org>

http://www.cgsecurity.org


Disk /dev/rdisk0 - 500 GB / 465 GiB - 977105060 sectors (RO)

Partition Start End Size in sectors

D Mac HFS 684392714 685662473 1269760

D Mac HFS 684392954 685662713 1269760

D Mac HFS 684393154 685662913 1269760

D Mac HFS 684393394 685663153 1269760

D Mac HFS 684393594 685663353 1269760

D Mac HFS 684393834 685663593 1269760

D Mac HFS 684394034 685663793 1269760

D Mac HFS 684394274 685664033 1269760

D Mac HFS 685647724 686917483 1269760

D MS Data 685647872 977104888 291457017

>D MS Data 801325056 977104895 175779840

D Mac HFS 801947710 810336319 8388610 [ D^A]

Structure: Ok. Use Up/Down Arrow keys to select partition.

Use Left/Right Arrow keys to CHANGE partition characteristics:

P=Primary D=Deleted

Keys A: add partition, L: load backup, T: change type, P: list files,

Enter: to continue

NTFS, blocksize=4096, 89 GB / 83 GiB


TestDisk 7.0, Data Recovery Utility, April 2015

Christophe GRENIER <grenier@cgsecurity.org>

http://www.cgsecurity.org


MS Data 801325056 977104895 175779840




Can't open filesystem. Filesystem seems damaged.

Aug 12, 2015 5:06 PM in response to Loner T

Thank you...after what seemed like an eternity, the deep search finished. The good news (I think) is I ran list files:



TestDisk 7.0, Data Recovery Utility, April 2015

Christophe GRENIER <grenier@cgsecurity.org>

http://www.cgsecurity.org

MS Data 685647872 977104888 291457017

Directory /


dr-xr-xr-x 0 0 0 26-Oct-2014 13:16 .

dr-xr-xr-x 0 0 0 26-Oct-2014 13:16 ..

dr-xr-xr-x 0 0 0 7-Feb-2014 13:09 $Recycle.Bin

dr-xr-xr-x 0 0 0 7-Feb-2014 17:44 6a164a97bdde17c02ef811

dr-xr-xr-x 0 0 0 26-Oct-2014 13:16 96bbef574cc6ea19ec3b83ad0a63

dr-xr-xr-x 0 0 0 7-Feb-2014 20:46 Boot

dr-xr-xr-x 0 0 0 7-Feb-2014 13:06 Intel

dr-xr-xr-x 0 0 0 13-Jul-2009 23:20 PerfLogs

dr-xr-xr-x 0 0 0 7-Feb-2014 13:48 Program Files

dr-xr-xr-x 0 0 0 19-Oct-2014 11:08 Program Files (x86)

dr-xr-xr-x 0 0 0 19-Oct-2014 11:09 ProgramData

dr-xr-xr-x 0 0 0 7-Feb-2014 13:01 Recovery

>dr-xr-xr-x 0 0 0 26-Oct-2014 13:14 System Volume Information

dr-xr-xr-x 0 0 0 7-Feb-2014 13:04 Users

Next

Use Right to change directory, h to hide Alternate Data Stream

q to quit, : to select the current file, a to select all files

C to copy the selected files, c to copy the current file


In an earlier post you said seeing the System Volume Information line would be a good thing. What shall I do now? Thank you again for your help.

Aug 12, 2015 5:16 PM in response to bjn1001

Yes, that is what we are looking for.

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. 685647872 ( - Start offset in sectors or the start point for Bootcamp part)
  8. +291457017 ( - 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.

  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.

Aug 12, 2015 6:59 PM in response to Loner T

So far so good...I think. Do I need to reboot (and hence close TestDisk and the gDisk terminals) between:


Deleting and re-write the GPT partition info for /dev/disk0s4. (successfully completed now, see below)

and Rebuilding MBR to match the new GPT information thus resetting the Hybrid MBR?



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/rdisk0: 977105060 sectors, 465.9 GiB

Logical sector size: 512 bytes

Disk identifier (GUID): CB0ED0E5-0692-47EE-ADA5-A01FDCCFFE98

Partition table holds up to 128 entries

First usable sector is 34, last usable sector is 977105026

Partitions will be aligned on 8-sector boundaries

Total free space is 115677465 sectors (55.2 GiB)


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

1 40 409639 200.0 MiB EF00 EFI System Partition

2 409640 684377967 326.1 GiB AF05 Macintosh HD

3 684377968 685647727 620.0 MiB AB00 Recovery HD

4 801325056 977104895 83.8 GiB 0700 BOOTCAMP


Command (? for help): d

Partition number (1-4): 4


Command (? for help): n

Partition number (4-128, default 4): 4

First sector (34-977105026, default = 685647728) or {+-}size{KMGTP}:685647872 First sector (34-977105026, default = 685647728) or {+-}size{KMGTP}: 685647872

Last sector (685647872-977105026, default = 977105026) or {+-}size{KMGTP}: +291457017

Current type is 'Apple HFS/HFS+'

Hex code or GUID (L to show codes, Enter = AF00): 0700

Changed type of partition to 'Microsoft basic data'


Command (? for help): p

Disk /dev/rdisk0: 977105060 sectors, 465.9 GiB

Logical sector size: 512 bytes

Disk identifier (GUID): CB0ED0E5-0692-47EE-ADA5-A01FDCCFFE98

Partition table holds up to 128 entries

First usable sector is 34, last usable sector is 977105026

Partitions will be aligned on 8-sector boundaries

Total free space is 288 sectors (144.0 KiB)


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

1 40 409639 200.0 MiB EF00 EFI System Partition

2 409640 684377967 326.1 GiB AF05 Macintosh HD

3 684377968 685647727 620.0 MiB AB00 Recovery HD

4 685647872 977104888 139.0 GiB 0700 Microsoft basic data


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/rdisk0.

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.

Aug 12, 2015 8:53 PM in response to Loner T

It worked!! I see Bootcamp in Finder and was able to boot into it and then back into my Mac. Importantly, all my files appear intact!

I went to 3 different tech "experts" and no one could figure this out. Honestly, thank the cyber Gods for people like LonerT who give their time freely to help tech neophytes like myself. Thank you again LonerT!! 🙂

Bootcamp Partition Lost After Yosemite Upgrade

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