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fhornedo Author

Level 1

0 points

Yosemite Upgrade Broke Bootcamp

Upgraded to Yosemite and now when I ALT Boot Windows 7 and Recovery partitions no longer show up. Using information from other threads I managed to get my Windows 7 partition to show up but when I select it I receive an ERROR READING DISK message. Is there any way to get this fixed?

diskutil list

/dev/disk0

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *750.2 GB disk0

1: EFI EFI 209.7 MB disk0s1

2: Apple_CoreStorage 647.3 GB disk0s2

3: Apple_Boot Recovery HD 650.0 MB disk0s3

4: Microsoft Basic Data 61.0 GB disk0s4

/dev/disk1

#: TYPE NAME SIZE IDENTIFIER

0: Apple_HFS Mac HD *647.0 GB disk1

Logical Volume on disk0s2

EE76C469-0C14-4592-986A-81FA25FAAF17

Unencrypted

diskutil cs list

CoreStorage logical volume groups (1 found)

+-- Logical Volume Group 02310D8F-058E-4CCF-8B7F-DAAED96FD1EF

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

Name: Mac HD

Status: Online

Size: 647348539392 B (647.3 GB)

Free Space: 18927616 B (18.9 MB)

+-< Physical Volume 0ABB2748-5135-4046-ACBB-5768C422F26B

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

| Index: 0

| Disk: disk0s2

| Status: Online

| Size: 647348539392 B (647.3 GB)

+-> Logical Volume Family 067A450C-844D-4465-8F8B-3DF65E5E2FF9

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

Encryption Status: Unlocked

Encryption Type: None

Conversion Status: NoConversion

Conversion Direction: -none-

Has Encrypted Extents: No

Fully Secure: No

Passphrase Required: No

+-> Logical Volume EE76C469-0C14-4592-986A-81FA25FAAF17

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

Disk: disk1

Status: Online

Size (Total): 646977290240 B (647.0 GB)

Conversion Progress: -none-

Revertible: Yes (no decryption required)

LV Name: Mac HD

Volume Name: Mac HD

Content Hint: Apple_HFS

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 1264352616 2 GPT part - 53746F72-6167-11AA-AA11-00306543ECAC

1264762256 1269536 3 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC

1266031792 79977296

1346009088 119138304 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 0 0 2 - 25 127 14 [ 1 - 409639] <Unknown ID>

2: AF 25 127 15 - 1023 254 63 [ 409640 - 1264352616] HFS+

3: AB 1023 254 63 - 1023 254 63 [1264762256 - 1269536] Darwin Boot

*4: 0C 1023 254 63 - 1023 254 63 [1346009088 - 119138304] Win95 FAT32L

Macbook Pro, Mac OS X (10.5.5)

Posted on Oct 22, 2014 5:54 PM

69 replies

fhornedo Author

Level 1

0 points

Oct 23, 2014 4:11 PM in response to Loner T

So use these values?

Start 1266032640

Finish 1465147384

Loner T

Level 9

59,513 points

Oct 23, 2014 4:16 PM in response to fhornedo

Yes, please. for GPT#4. Remember d,4,n,4,Start,End in GPT Fdisk.

fhornedo Author

Level 1

0 points

Oct 23, 2014 7:33 PM in response to Loner T

Loner T, I cant figure out how to use GDisk (sorry for my ignorance). What do I do?

Loner T

Level 9

59,513 points

Oct 24, 2014 3:37 AM in response to fhornedo

Take a look at the following example. You need to use your own start/end rather than what is here...

Post back when you are ready for Step 5.

"Please stop if you see any error messages.

1. Delete the old entry and create a new entry at GPT#4.

sudo gdisk /dev/disk0

86923264

538218489

0700

2. You will need to reboot after the change, because the disk you are booted from is the one being modified. Reboot will rebuild disk0s4 using the start/end you entered.

3. Run the dd command - sudo dd if=/dev/rdisk0s4 count=1 2>/dev/null | hexdump -C and check that the first line contains "R.NTFS".

4. This is a tedious process and you want to check after the second 'p'rint command that it looks reasonable, before the 'w'rite and 'y'es to confirm.

5. Once you a working GPT#4, a new hybrid MBR needs to be created which will overwrite what you see in your Fdisk output. This is also done using GPT Fdisk (Gdisk).

6. a. Test 1 - Can you see your Bootcamp volume in Finder.

b. Test 2 - Can you files in the Bootcamp volume?

c. Test 3 - Can you see Bootcamp in your System Preferences -> Startup Disk.

d. Test 4 - If Test 1-3 are successful, select Bootcamp and click on Restart. You may need Windows startup repair, if you see a hanging underline cursor at the top left corner of your screen. In most cases, it is not required.

Here is an example...

Command (? for help): d

Partition number (1-4): 4

Command (? for help): n

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

First sector (34-1954210086, default = 1454210080) or {+-}size{KMGTP}: 1454211072

Last sector (1454211072-1954210086, default = 1954210086) or {+-}size{KMGTP}: 1954209791

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/disk0: 1954210120 sectors, 931.8 GiB

Logical sector size: 512 bytes

Disk identifier (GUID): 6ED0C429-00D1-4759-B50E-04B6FB80D0E3

Partition table holds up to 128 entries

First usable sector is 34, last usable sector is 1954210086

Partitions will be aligned on 8-sector boundaries

Total free space is 1293 sectors (646.5 KiB)

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

1 40 409639 200.0 MiB EF00 EFI System Partition

2 409640 1452940543 692.6 GiB AF00 Customer

3 1452940544 1454210079 619.9 MiB AB00 Recovery HD

4 1454211072 1954209791 238.4 GiB 0700 Microsoft basic data

fhornedo Author

Level 1

0 points

Oct 24, 2014 8:36 AM in response to Loner T

Ok I think i'm ready for step 5. Here is what it looks like now:

Loner T

Level 9

59,513 points

Oct 24, 2014 8:51 AM in response to fhornedo

1. Can you reboot and post the output of

sudo gpt -vv -r show /dev/disk0

sudo fdisk /dev/disk0

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

as well? This will ensure that the GPT has been written and committed across power cycles.

The screen shot will break in next few hours when the Discussions will stop showing the image?

2. 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.

fhornedo Author

Level 1

0 points

Oct 24, 2014 2:25 PM in response to Loner T

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 1264352616 2 GPT part - 53746F72-6167-11AA-AA11-00306543ECAC

1264762256 1269536 3 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC

1266031792 79977296

1346009088 119138304 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 0 0 2 - 25 127 14 [ 1 - 409639] <Unknown ID>

2: AF 25 127 15 - 1023 254 63 [ 409640 - 1264352616] HFS+

3: AB 1023 254 63 - 1023 254 63 [1264762256 - 1269536] Darwin Boot

*4: 07 1023 254 63 - 1023 254 63 [1346009088 - 119138304] HPFS/QNX/AUX

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

-bash: ?dev/null: No such file or directory

Loner T

Level 9

59,513 points

Oct 24, 2014 2:56 PM in response to fhornedo

1. Your start/end of Start 1266032640 / Finish 1465147384

do not seem to be the same as

1266031792 79977296

1346009088 119138304 4 GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7

and

4: 07 1023 254 63 - 1023 254 63 [1346009088 - 119138304] HPFS/QNX/AUX

You will need to redo Step 1 (recreate the GPt#4 again).

2. Your dd command has an extra "?", it should be

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

and this would make sense after what is in 1.

fhornedo Author

Level 1

0 points

Oct 25, 2014 9:57 AM in response to Loner T

Ok this is what I have now. Interestingly, I can now see my Bootcamp drive on my desktop and in Finder but when I tried to boot to it I received a NO BOOTABLE DEVICE error.

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 1264352616 2 GPT part - 53746F72-6167-11AA-AA11-00306543ECAC

1264762256 1269536 3 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC

1266031792 848

1266032640 199114745 4 GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7

1465147385 1750

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 - 1264352616] HFS+

3: AB 1023 254 63 - 1023 254 63 [1264762256 - 1269536] Darwin Boot

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

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 20 76 4b |........?.... vK|

00000020 00 00 00 00 80 00 80 00 f8 3f de 0b 00 00 00 00 |.........?......|

00000030 fb 02 00 00 00 00 00 00 fa 02 00 00 00 00 00 00 |................|

00000040 f6 00 00 00 01 00 00 00 30 20 3b 2c ee b5 cf 01 |........0 ;,....|

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

Loner T

Level 9

59,513 points

Oct 25, 2014 9:52 AM in response to fhornedo

1. You need to recreate the Hybrid MBR using Gdisk. See the step 5 Example earlier.

2. The command is sudo dd if=/dev/rdisk0s4 count=1 2>/dev/null | hexdump -C. You still have the "?" instead of "/". 😉

fhornedo Author

Level 1

0 points

Oct 25, 2014 10:19 AM in response to Loner T

It worked!! Loner T you are the best! Thanks for everything!

fhornedo Author

Level 1

0 points

Oct 25, 2014 10:36 AM in response to Loner T

One last question. How do I get the Recovery drive set back up on the MBR?

Loner T

Level 9

59,513 points

Oct 25, 2014 11:45 AM in response to fhornedo

If you look at the third entry of the Fdisk output, it is your Recovery HD for OSX and will show up as an option. Command+R will invoke recovery when pressed during boot up if pressed after the boot chime. OSX does not use MBR for Recovery, the GPT is used. I suggest you back up Windows to an external drive using Windows backup.

fhornedo Author

Level 1

0 points

Oct 25, 2014 11:49 AM in response to Loner T

Sounds good. Thanks again!

fhornedo Author

Level 1

0 points

Oct 25, 2014 12:36 PM in response to Loner T

Loner T, it looks like the Recovery partition is not showing up as an option when I OPTION boot but it used to. Should I use GDISK to make the partition bootable?

Yosemite Upgrade Broke Bootcamp