Bootcamp won't load after adding partition to Lion

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BrianRandell Author

Level 1

0 points

Bootcamp won't load after adding partition to Lion

How things started

13" MacBook Air mid-2011

Mac OS X Lion 10.7.5 (11G63b) with 256gb SSD

HDD partition between OS/X and a BOOTCAMP partition running Windows 7 SP1 x64 Ultimate

I updated both OSes with the latest drivers.

In Lion, I did (disabled now) have v.9.5.2 of Paragon's NTFS driver installed (which I forgot about before I started down the path I'm on).

What I did:

After doing a time machine backup of Lion, Disk Utility was reporting very little free space on OS/X. I ended up having to run Repair from the Recovery Partition. Once I did that OS/X and Windows were both booting fine and I had > 180 GB of free space on my OS/X partition.

I created a 48 GB partition as follows:

I then formatted it last night, etc. Today upon restarting I can't boot into Windows on Boot Camp.

First it didn't show up on the Start Up selector when holding down the Option key. I then started looking. I set Boot Camp as start up in the Paragon applet and this allowed it to boot into Boot Camp but then I get the ...

No bootable device --- insert boot disk and press any key

... error.

So I found the magic thread with Christopher Murphy's advice so I'm looking for help.

Here's the results of running the commands from Lion that he has asked other to do:

sudo gpt -r -vv show disk0

gpt show: disk0: mediasize=251000193024; sectorsize=512; blocks=490234752

gpt show: disk0: PMBR at sector 0

gpt show: disk0: Pri GPT at sector 1

gpt show: disk0: Sec GPT at sector 490234751

start size index contents

0 1 PMBR

1 1 Pri GPT header

2 32 Pri GPT table

34 6

40 409600 1 GPT part - C12A7328-F81F-11D2-BA4B-00A0C93EC93B

409640 323832816 2 GPT part - 48465300-0000-11AA-AA11-00306543ECAC

324242456 1269536 3 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC

325511992 92868000 4 GPT part - 48465300-0000-11AA-AA11-00306543ECAC

418379992 1269544 5 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC

419649536 70584320 6 GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7

490233856 863

490234719 32 Sec GPT table

490234751 1 Sec GPT header

sudo fdisk /dev/disk0

Disk: /dev/disk0 geometry: 30515/255/63 [490234752 sectors]

Signature: 0xAA55

Starting Ending

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

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

1: EE 1023 254 63 - 1023 254 63 [ 1 - 490234751] <Unknown ID>

2: 00 0 0 0 - 0 0 0 [ 0 - 0] unused

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

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

Thank you for any help you may be able to provide!

Cheers,

Brian

MacBook Air, Mac OS X (10.7.5)

Posted on Aug 1, 2013 12:49 PM

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Answer 1

Best reply

Christopher Murphy

Level 3

560 points

Aug 1, 2013 1:36 PM in response to BrianRandell

Understand that MBRs only hold 4 primary partition entries, the Windows bootloader (on BIOS hardware) only supports booting from a primary partition. Because you have six partitions, there isn't a single "correct" way to create a hybrid MBR. Any hybrid MBR for your scenario will not match up with the partitions in the GPT, meaning there's risk for data loss at any time, and while I don't have direct evidence (yet) I suspect the OS X installer does a 'diskutil repairDisk' which likely would alter one or both partition maps. Ergo, your layout is unsupported, so if you're going to continue to use it, you need to learn something how to maintain it when things like this happen.

So what you need to do is download and install GPT fdisk (gdisk) from sourceforge, and create a new hybrid MBR. What I would do is ONLY add GPT partition 6 to the hybrid MBR as entry #2, and mark it bootable and add no additional entries to the MBR. As a result, gdisk will create an MBR with two entries: one 0xEE entry for the sectors comprising the GPT, EFI System, and the next four OS X related partitions. And one 0x07 entry for Windows, also marked bootable. It should be that most utilities are aware of the meaning of 0xEE and will not modify it.

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Answer 2

BrianRandell Author

Level 1

0 points

Aug 1, 2013 2:34 PM in response to Christopher Murphy

Hello Christopher,

Thank you for the reply. I *tried* to do what you said. In doing so Windows booted. :-)

However, I somehow didn't do it right and destroyed everything else--when holding down the Option key only Windows showed up. :-(

The good news is I was able to boot off my TIme Machine backup drive, run Disk Util and repair things which put me back to where I started.

For now, I think I'm just going to leave well enough alone until I go back to a single OS/X partition. I've got everything I need off of Windows.

I appreciate your time and answer.

Cheers,

Brian

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Answer 3

RH ADAM

Level 1

10 points

Aug 1, 2013 2:51 PM in response to BrianRandell

Here you go,

as Christopher said,

1 - Download gdisk, a.k.a. GPT fdisk.

2 - Go to Terminal and enter : sudo gdisk /dev/disk0

If you got any error don't proceed further and report the error messages

3 - Proceed as follow;

r <enter> go to the recovery & transformation menu

h <enter> create a new hybrid MBR

6 <enter> add partion 6 to the MBR

y <enter> Place EFI GPT (0xEE) partition first in MBR (good

for GRUB)?

<enter> accept the default MBR hex code of 07

y <enter> set the bootable flag

n <enter> do not protect more partitions

w <enter> write partition table to disk

If everything went well you should see : Disk synchronization succeeded

4- reboot your mac : sudo reboot

This should fix it

Good luck

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Answer 4

BrianRandell Author

Level 1

0 points

Aug 1, 2013 5:23 PM in response to RH ADAM

RH ADAM and Christopher:

Here was the critical line I messed up:

y <enter> Place EFI GPT (0xEE) partition first in MBR (good for GRUB)?

Once I re-did things all is good (Windows did want to run a CHKDSK) but now all is happy.

I truely appreciate your help! Thank you!

Brian

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