Viewing OSX partition from Bootcamp

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Viewing OSX partition from Bootcamp

After partitioning my Hard drive (post installing my bootcamp partition), I was unable to boot from my Bootcamp partition. Which was fixed by following the instructions in this thread. After launching my bootcamp partition again I was unable to view my OSX and Storage partitions whilst on my windows partition.

sudo gpt -r -vv show disk0

gpt show: disk0: mediasize=320072933376; sectorsize=512; blocks=625142448
gpt show: disk0: Suspicious MBR at sector 0
gpt show: disk0: Pri GPT at sector 1
gpt show: disk0: Sec GPT at sector 625142447
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 294655544 2 GPT part - 48465300-0000-11AA-AA11-00306543ECAC
295065184 1269536 3 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC
296334720 640
296335360 135448576 4 GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7
431783936 193357824 5 GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7
625141760 655
625142415 32 Sec GPT table
625142447 1 Sec GPT header

sudo fdisk /dev/disk0

Disk: /dev/disk0 geometry: 38913/255/63 [625142448 sectors]

Signature: 0xAA55

Starting Ending

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

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

1: EE 0 0 2 - 1023 254 63 [ 1 - 431783935] <Unknown ID>

*2: 07 1023 254 63 - 1023 254 63 [ 431783936 - 193357824] HPFS/QNX/AUX

3: 00 0 0 0 - 0 0 0 [ 0 - 0] unused

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

MacBook Pro, OS X Mountain Lion (10.8.4), WIndows 7 32-bit

Posted on Dec 19, 2013 6:58 PM

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Answer 1

Best reply

alprao

Level 1

10 points

Dec 19, 2013 11:40 PM in response to TimERTy

I have just the same problem after have fixed the bootcamp following the instructions in this thread.

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Answer 2

Loner T

Level 9

59,471 points

Dec 20, 2013 1:29 PM in response to TimERTy

Your MBR is not correct. Alprao has the same issue if his fdisk output is similar to yours.

I would suggest both of you look at this https://discussions.apple.com/thread/5641066 and check the steps for creating a hybrid MBR and correcting it with appropriate start/end/size information.

The current layout both of you have, with an additional NTFS partition, is unsupported and Software Update may cause future problems for you.

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Answer 3

Dec 25, 2013 9:47 AM in response to TimERTy

Right, so the problem is that the MBR only contains the Windows partition, therefore Windows only sees itself. To fix this, you'd use gdisk to create a new hybrid MBR. Go to the recovery menu, r, create new hybrid MBR, h. And then follow the questions: yes to EFI GPT being first in the MBR; add partitions 2 4 5. Accept default type code hex values by just hitting enter when asked, and do not make 2 or 4 bootable, do make 5 bootable.

So the problem with this layout is that partition 3, Recovery HD, can't be added to the MBR. Therefore it appears to Windows as unallocated free space and is open game for being modified, erased, whatever. Which is why a 5 partition layout isn't recommended or supported and also has no meaningful advantage. But I'd fix it as suggested and just leave it alone until you have full backups of both environments and you're ready to do a major upgrade and blow everything away and start from scratch at that time. It's a fairly low risk that Recovery HD gets broken by Windows. And it's sort of risky to try to get rid of this extra partition you created, to go back to a 4 partition layout.

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