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Boot Camp won't start after OSX Yosemite upgrade

Like so many others, I installed OSX Yosemite this morning and now Boot Camp no longer works.


After I updated to Yosemite I restarted my computer, held down alt, and was presented nothing but a Macintosh HD. I followed “Loner T’s” instructions…


ndiskutil list

diskutil cs list

sudo gpt -vv -r show /dev/disk0

sudo fdisk /dev/disk0

Enter you password when prompted.


…and now a windows option is available during startup. However, when selected, all I get is a black screen with "A disk read error occurred" notice.


I’m in serious trouble if I cannot repair this issue. PLEASE HELP.

iMac, OS X Yosemite (10.10), Windows 7

Posted on Oct 18, 2014 12:00 PM

Reply
59 replies

Oct 18, 2014 1:38 PM in response to Loner T

Yes, here they are...


James-iMac:~ SIGMA$ diskutil list

/dev/disk0

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *1.0 TB disk0

1: EFI EFI 209.7 MB disk0s1

2: Apple_HFS Macintosh HD 572.0 GB disk0s2

3: Apple_Boot Recovery HD 650.0 MB disk0s3

4: Microsoft Basic Data 102.9 GB disk0s4

James-iMac:~ SIGMA$ diskutil cs list

No CoreStorage logical volume groups found

James-iMac:~ SIGMA$ sudo gpt -vv -r show /dev/disk0

Password:

gpt show: /dev/disk0: mediasize=1000204886016; sectorsize=512; blocks=1953525168

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 1953525167

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 1117208056 2 GPT part - 48465300-0000-11AA-AA11-00306543ECAC

1117617696 1269544 3 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC

1118887240 633737912

1752625152 200898560 4 GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7

1953523712 1423

1953525135 32 Sec GPT table

1953525167 1 Sec GPT header

James-iMac:~ SIGMA$ sudo fdisk /dev/disk0

Disk: /dev/disk0 geometry: 121601/255/63 [1953525168 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 - 1117208056] HFS+

3: AB 1023 254 63 - 1023 254 63 [1117617696 - 1269544] Darwin Boot

*4: 07 1023 254 63 - 1023 254 63 [1752625152 - 200898560] HPFS/QNX/AUX

James-iMac:~ SIGMA$

Oct 18, 2014 2:04 PM in response to Baja Tym

Do a quick search, which is unlikely to return anything since there was no NTFS header to begin with. If the NTFS header was correct you would have been able to see files using "P: List Files". In the Testdisk step-by-step wiki, there is a deeper search, which is what is needed. It is a slow, tedious and time-consuming operation. You can also see the steps for deeper search in Bootcamp missing after expanding partition.

Boot Camp won't start after OSX Yosemite upgrade

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