Repairing Boot Camp after creating new partition

https://discussions.apple.com/thread/5190331

Hi everyone,

First, I'd like to thank @Scotch_Brawth for pointing up the question, and @Christopher Murphy, because after looking through the multiple resolved cases I found a similar one to mine.. and It worked just fine 🙂

The problem is that after starting windows I couldn't view neither Macintosh HD, nor the new partition (HYBRIDE) .

Knowing Before the problem occur, I've had ReadOnly rights to Macintosh HD from windows.

So if possible, how could I visualise Macintosh HD and HYBRIDE partitions in windows.

Thanks in advance and have a great day/night

https://discussions.apple.com/thread/5198245

Again thanks in advance

Christopher Murphy,

Based on your ealier comments, I've posted a new thread with my details.

https://discussions.apple.com/thread/5209338

Any help is appreciated.

Thank you.

Brian

I listed something I shouldn't have in the thread so it might get deleted. :-(

I'll create a new post if that happens.

Sorry for the noise.

Christopher Murphy,

Please see this post if you have a moment.

https://discussions.apple.com/thread/5209547

Sorry for the extra post and noise.

Any help appreciated it.

Brian

This feels feels more than a little gauche to abuse the reply system like this, but frankly Christopher Murphy, I fear you're my Obi-Wan... my only hope.

Can you take a look at my FDISK and GPT results and let me know if I've got hope of recovering my Boot Camp MBR?

https://discussions.apple.com/thread/5232082

I haven't read all 44 pages of this thread so maybe this has been addressed but here's what I'm trying to accomplish. I run bootcamp and Parallels (the latter using the bootcamp installation as the guest OS) on a 15" rMBP with 256GB SSD. I use Win8 as the guest OS and Mountain Lion on the host. I have been trying to enable bitlocker in the guest OS and when I attempt to create another partition (required with bitlocker on a system drive) using the Win8 command:

BdeHdCfg.exe -target c: shrink -newdriveletter x: -size 1500 -quiet –restart

I receive the error:

Disk already has the maximum number of primary and extended partitions. Use the

'-driveinfo' command for a list of valid target drives.

This of course is related to the issue originally noted in this thread about hybrid MBR as I already have all four allowed partitions. It looks like there may be a way around this using some of the techniques described in this thread however rather than creating another partition visible to OSX (which is what OP did) I want to create two partitions visible to Win8. Would someone be so kind as to walk through how I would accomplish that?

Thank you!

Edit: in hopes of increasing the Google-ability of this thread for future people with this issue, Bitlocker Drive Encryption returns the message "Bitlocker Setup could not find a target system drive. You may need to manually prepare your drive for Bitlocker." The Event Log contains the following errors in the Bitlocker-DrivePreparationTool log:

Error Code: 0xC0A00007

Error Text: BitLocker Setup could not find a target system drive. You may need to manually prepare your drive for BitLocker.

and

A volume failed to meet the requirements for a target volume.

Volume Name: \\?\GLOBALROOT\Device\HarddiskVolume4

Reason: The system drive cannot be used for the merge operation.

I don't know exactly how Bitlocker works, but if it's anything like FDE on OS X or Linux, then it requires an unencrypted boot volume (which I think Microsoft weirdly calls a system volume, whereas the much larger system volume with the main OS and application files that ends up being encrypted is called a boot volume). This uncrypted smallish (~100MB) system volume for booting must be a primary partition. I'm pretty sure the Windows boot volume (the big daddy with all files, and is encrypted) can be on an extended partition. However the problem with this is that extended partitions exist in a primary partition. So you need to use one of the primary partitions to define extended partitions, and you need a primary partition to boot from. Yet you only have one primary partition available because Apple uses three primary partitions.

The Apple hybrid MBR is already a non-standard, ill-advised, flakey, error prone thing. Doing it differently will make it even more non-standard and prone to problems. But if you can avoid using *any* OS X or Windows disk utilities, and understand that major OS upgrades likely will cause the hybrid MBR to be removed causing what appears to be data loss, you might be able to avoid problems and do what you want. But the bottom line is that Apple isn't supporting your use case at all. To do that, they need to support UEFI booting Windows, so that Windows will use the same GPT OS X does, instead of depending on hybrid MBRs.

You can create a hybrid MBR with its first partition defined by the sectors making up: the GPT itself, EFI System partition, OS X, and Recovery HD, with a type code of 0xEE "GPT Protective partition". So instead of listing out each GPT partition as separate (and sync'd) MBR partitions, you're going to say the GPT itself and the first three GPT partitions, are defined as one partition in the MBR. Since it's type 0xEE, nothing that understands only MBR should touch those sectors, including Windows.

Now you have three primary partitions remaining. One of which can be the unencrypted system volume for Windows, and one of which can be the boot volume that's encrypted and contains everything else. It actually leaves you with one primary partition slot available in the MBR which you could make extended partitions from, but in this scenario it isn't needed and isn't advised to combine GPT, MBR primary and extended partitions.

The thing to keep in mind is you MUST do all of the partition work in advance on the GPT first. You need to get that layout correct in the GPT, and then after all of it's correct, then you make the hybrid MBR from the GPT. And you need to be prepared to make a new hybrid MBR because at any time it seems, something OS X related can nuke that hybrid MBR apparently on a whim. So you'll also need to keep good backups.

So if you understand all of this, and are prepared procede despite the consequences, namely knowing more about MBR and GPT that you probably want to know, then I suggest posting a new thread and then copying the URL in this thread. This thread is too cluttered to discuss Bitlocker setups. In that thread just summarize what you want to accomplish (a shorter version of what you posted), and also include the result from your current MBR and GPT using commands:

sudo gpt -r -v show disk0

sudo fdisk /dev/disk0

continuing the discussion here: https://discussions.apple.com/thread/5245031

Hi Christopher Murphy,

When I use the command - sudo gdisk /dev/disk0

I get -bash: gdisk: command not found

Can you please help me on that? I so didn't want to add more and more to this thread but I am helpless at this point.

Thanks in advance.

Hi Scotch_Brawth,

The command - sudo gdisk /dev/disk0 returns -bash: gdisk: command not found

Can you help me?

Download and install gdisk.

Hey guys,

I couldn't quite wrap my head around the instructions on the first page. Could someone please help me out? Here's what I have: one HDD with 3 partitions: OS X 10.8, Mavericks, and Windows:

Results for "gdisk of disk0":

Disk /dev/disk0: 977105060 sectors, 465.9 GiB

Logical sector size: 512 bytes

Disk identifier (GUID): A55F90BA-7313-475D-B39E-D1F27D04A0B6

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 173377009 sectors (82.7 GiB)

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

1 40 409639 200.0 MiB EF00 EFI System Partition

2 409640 488690887 232.8 GiB AF00 Customer

3 488690888 489960423 619.9 MiB AB00 Recovery HD

4 662568112 818818111 74.5 GiB AF00 Mavericks

5 818818112 820087647 619.9 MiB AB00 Recovery HD

6 820856832 977104895 74.5 GiB 0700 WINDOWS

Result for "sudo gpt -r -vv show disk0":

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

gpt show: disk0: PMBR at sector 0

gpt show: disk0: Pri GPT at sector 1

gpt show: disk0: Sec GPT at sector 977105059

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 488281248 2 GPT part - 48465300-0000-11AA-AA11-00306543ECAC

488690888 1269536 3 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC

489960424 172607688

662568112 156250000 4 GPT part - 48465300-0000-11AA-AA11-00306543ECAC

818818112 1269536 5 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC

820087648 769184

820856832 156248064 6 GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7

977104896 131

977105027 32 Sec GPT table

977105059 1 Sec GPT header

And lastly, results for "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 - 977105059] <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

10.8 and Mavericks partitions work fine, Windows just won't boot. I can still access all the files via working OS's. I just want to restore windows and make it bootable.

I also have rEFIt installed, not sure if that makes any difference. I hope somebody out there who knows all about this can help me out. I would be very very greatful! Thanks so much 🙂

As you can see from the results, you have six partitions, not three. It's just that three of them aren't visible in the GUI.

Apple's utilities will not create the required hybrid MBR for Windows when there are more than 4 partitions. So what you want to do is not supported by Apple.

At risk of present and future data loss, you could use gdisk to create a hybrid MBR with only partition 6 added. That will cause it to make an MBR with partition 1 comprised of GPT partitions 1 through 5. And GPT partition 6 will be defined in the MBR as partition 2. You need to make that partition bootable as well.

The answer to this question is yes:

Place EFI GPT (0xEE) partition first in MBR (good for GRUB)? (Y/N):

If you make any partition changes at all with Disk Utility, or if it turns out the current or future OS installer tries to fix such unsync'd MBR and GPTs (which I suspect is true based on other reports in these forums), realize that the hybrid MBR will be overwritten with a protective MBR, rendering Windows unbootable again, and you'll need to make a new hybrid MBR with gdisk.

If you make any partition changes in Windows, realize this will risk totally hosing everythign on the computer because Windows (correctly) only recognizes the hybrid MBR, and will at best not update the GPT at all, and at worst will end up corrupting all or part of it, rendering OS X broken.

Make use of the gdisk backup option, to keep a copy of the current state of both partition maps should it get messed up in the future.