Windows partition not bootable after update.

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Windows partition not bootable after update.

All, As per a few others, I'm unable to boot into windows after an update.

In system preferences, under startup disk, only the OS X drive is shown.

The disk utility does show my 'MacDoze' drive greyed out. This drive was changed to a 3tb unit about a year ago and has been dual booting just fine.

diskutil list gives me the following:-

192168015007:~ pom$ diskutil list

/dev/disk0

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *3.0 TB disk0

1: EFI EFI 209.7 MB disk0s1

2: Apple_HFS Macintosh HD 100.2 GB disk0s2

3: Apple_Boot Recovery HD 650.0 MB disk0s3

4: Microsoft Basic Data MacDoze 399.0 GB disk0s4

5: Microsoft Basic Data 0 B disk0s5

192168015007:~ pom$

and diskutil cs list as below:-

192168015007:~ pom$ diskutil cs list

No CoreStorage logical volume groups found

192168015007:~ pom$

sudo gpt -vv -r show /dev/disk0 results below:-

gpt show: /dev/disk0: mediasize=3000592982016; sectorsize=512; blocks=5860533168

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 5860533167

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 195797056 2 GPT part - 48465300-0000-11AA-AA11-00306543ECAC

196206696 1269536 3 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC

197476232 120

197476352 779296768 4 GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7

976773120 0 5 GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7

976773120 3318192128 4

4294965248 1565567887

5860533135 32 Sec GPT table

5860533167 1 Sec GPT header

Any and all assistance appreciated.

Cheers.

iMac, OS X Yosemite (10.10.4)

Posted on Jul 1, 2015 6:01 PM

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Answer 1

Loner T

Level 9

59,471 points

Jul 1, 2015 6:06 PM in response to Pom_VZ

When did it stop working? This is a non-Standard layout. You have two MSD partitions. Only one is supported, otherwise Software Upgrade will break MacDoze. Your GPT seems to have been manually manipulated. Please describe in detail how you got to this point.

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Answer 2

Pom_VZ Author

Level 1

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Jul 1, 2015 6:22 PM in response to Loner T

It was a standard 500g mac that the kids were using, and I upgraded the drive and installed windows 8 following a guide I dragged off the net a year or so ago.

All was going swimmingly till all the iMacs started doing the latest updates over the last day or so. Instead of downloading the update 5 times, (I've got a few macs) I grabbed the DMG off another machine, and stated the upgrade on this one. The update failed (after reboot and almost complete) giving a non specific reason.

I went to boot back into Windows and had no option to do so.

There was a complication with the drive upgrade as i purchased a 3tb drive, which apparently isn't supported, so some space had to be sacrificed. Can't remember what the issue was, but I couldn't utilise all the space.

Hope that sheds some more light.

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Answer 3

Loner T

Level 9

59,471 points

Jul 1, 2015 7:07 PM in response to Pom_VZ

Pom_VZ wrote:

All was going swimmingly till all the iMacs started doing the latest updates over the last day or so. Instead of downloading the update 5 times, (I've got a few macs) I grabbed the DMG off another machine, and stated the upgrade on this one. The update failed (after reboot and almost complete) giving

a non specific reason.

The updates can contain hardware-specific patches, so all updates may not be the same across hardware. The latest updates also have EFI firmware updates, so it can be a problem. For example, About the security content of Mac EFI Security Update 2015-001 - Apple Support is machine-specific.

I went to boot back into Windows and had no option to do so.

Do you have a mix of OSes on your Macs? For example, do you Mavericks or older on some, Yosemite on others? If yes, updates are not equivalent either.

Can you post the output of the following commands?

sudo fdisk /dev/disk0

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

The "sudo" commands will prompt for your password, and it will not be echoed back. You may also see a warning about improper use of "sudo" and potential data loss due to "abuse" of the command. These will show the MBR and the header on the MacDoze partition. The next step will be determined based on the output.

There was a complication with the drive upgrade as i purchased a 3tb drive, which apparently isn't supported, so some space had to be sacrificed. Can't remember what the issue was, but I couldn't utilise all the space.

On Macs prior to Late 2013 models, the only supported method of installing Windows is legacy BIOS. This uses a Hybrid MBR, which has limitations.

1. Windows cannot be installed outside the first 2TB boundary.

2. Windows and OSX (with two OSX hidden partitions) will not support resizing/repartitioning of disks.

3. To work around this, OSX will create a Logical Volume (after Mountain Lion) an dadd chunks of partitions to look like a single logical volume. It is a pain to manage and manipulate under normal circumstances.

4. You ended up sacrificing anything beyond the 2TB boundary, because you do not have a Fusion drive, which OSX will partition properly (most of the time 😉). It is perfectly usable disk space, but we need to get Windows up first.

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Answer 4

Pom_VZ Author

Level 1

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Jul 1, 2015 7:36 PM in response to Loner T

Excellent. Some things I didn't know in there.

All the macs are on the latest OS X. Two of the 27" are the same, one older. This 21" is the oldest of them all. Will make sure I download updates per machine in the future as I wasn't aware that firmware updates came in piggybacked.

sudo fdisk /dev/disk0 output

Disk: /dev/disk0 geometry: 97451/255/63 [1565565872 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 - 195797056] HFS+

3: AB 1023 254 63 - 1023 254 63 [ 196206696 - 1269536] Darwin Boot

*4: 07 1023 254 63 - 1023 254 63 [ 197476352 - 4097488896] HPFS/QNX/AUX

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 40 c5 0b |........?....@..|

00000020 00 00 00 00 80 00 80 00 ff b7 3a f4 00 00 00 00 |..........:.....|

00000030 00 00 0c 00 00 00 00 00 02 00 00 00 00 00 00 00 |................|

00000040 f6 00 00 00 01 00 00 00 8d 50 23 7c 6a 23 7c ca |.........P#|j#|.|

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 52 11 16 68 09 00 66 53 66 53 66 |h...hR..h..fSfSf|

00000100 55 16 16 16 68 b8 01 66 61 0e 07 cd 1a 33 c0 bf |U...h..fa....3..|

00000110 0a 13 b9 f6 0c fc f3 aa e9 fe 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 a1 f6 01 e8 09 00 |...u...fa.......|

00000170 a1 fa 01 e8 03 00 f4 eb fd 8b f0 ac 3c 00 74 09 |............<.t.|

00000180 b4 0e bb 07 00 cd 10 eb f2 c3 0d 0a 41 20 64 69 |............A di|

00000190 73 6b 20 72 65 61 64 20 65 72 72 6f 72 20 6f 63 |sk read error oc|

000001a0 63 75 72 72 65 64 00 0d 0a 42 4f 4f 54 4d 47 52 |curred...BOOTMGR|

000001b0 20 69 73 20 63 6f 6d 70 72 65 73 73 65 64 00 0d | is compressed..|

000001c0 0a 50 72 65 73 73 20 43 74 72 6c 2b 41 6c 74 2b |.Press Ctrl+Alt+|

000001d0 44 65 6c 20 74 6f 20 72 65 73 74 61 72 74 0d 0a |Del to restart..|

000001e0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|

000001f0 00 00 00 00 00 00 8a 01 a7 01 bf 01 00 00 55 aa |..............U.|

00000200

Appreciate the assistance.

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Answer 5

Loner T

Level 9

59,471 points

Jul 1, 2015 8:05 PM in response to Pom_VZ

Pom_VZ wrote:

*4: 07 1023 254 63 - 1023 254 63 [ 197476352 - 4097488896] HPFS/QNX/AUX

This Fdisk entry should match

197476352 779296768 4 GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7

Also, these entries seem to be corrupted.

976773120 0 5 GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7

976773120 3318192128 4

4294965248 1565567887

Here is a table that I use for verification. All these numbers are 512-byte sector addresses on the 3TB Disk. The index column in your GPT output should never have duplicates, but it does. GPT 3 is the entry at index 3, NTFS start matches in both the GPT and MBR.

GPT 3 Start	GPT 3 Size	GPT 3 End	NTFS Start	Sector Offset	NTFS Size	NTFS End	Sector Offset (MB)	NTFS(Gb)
196206696	1269536	197476232	197476352	120	4097488896	4294965247	0	1953.834961

The NTFS End number is 2,048 sectors less than (2**32 - 1) which is the 2TB limit.

1. Is you MacDoze size the same as the original on the 500Gb drive or was it expanded (by some partitioning tool) to use the remainder?

2. Based on the size value in the MBR entry #4, your NTFS should be about 1953 GB (~2TB). Is this correct?

3. GPT 5 with a size of 0 is where the upgrade process miscalculated the size. It still thinks you are on a 500GB disk.

4. The MBR thinks you are using roughly 2TB.

5. The GPT can be cleaned assuming the values in MBR are correct, based on what you can recall about the partition sizes and answers to 1 and 2.

6. How critical is this to be fixed tonight (US ET is my timezone)?

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Answer 6

Pom_VZ Author

Level 1

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Jul 1, 2015 8:50 PM in response to Loner T

My Macdoze partition is much larger than the original 500G. 2tb seems about right.

From memory, I let bootcamp size it originally, but then I tried to utilise all the space. I think I may have resized it under windows, but no third party tools used.

Not critical to get done now, but I do need to gain access to the data in that partition.

Happy to take instruction on cleaning the GPT, when you have time. I'll do some googling in the mean time.

Appreciated.

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Answer 7

Loner T

Level 9

59,471 points

Jul 1, 2015 9:06 PM in response to Pom_VZ

Please see BOOTCAMP Partition lost after some updates in Yosemite as an example. You need to download GPT Fdisk as indicated in the linked thread.

In your case, delete GPT 4 and GPT 5 (the 0 byte entry). The example only deletes entry 4 in first set of Gdisk steps at step 3 and 4. You will need d,4,d,5 sequence. and then create a GPT which has the NTFS start and size as shown in my table instead of the values in steps 7 and 8 (which are specific to the specific user in that thread). You do not need the second set of Gdisk steps because your MBR is the source of values for start/size anyway.

Please post back, but response may be delayed.

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Answer 8

Pom_VZ Author

Level 1

0 points

Jul 1, 2015 10:52 PM in response to Loner T

Understand you may be away, but this is testing the boarders of my experience, hence seeking confirmation.

You asked me to delete GPT 4 and 5, but 5 appears to be the Bootcamp partition?

Disk /dev/rdisk0: 5860533168 sectors, 2.7 TiB

Logical sector size: 512 bytes

Disk identifier (GUID): 00000E82-4754-0000-7204-0000CB700000

Partition table holds up to 128 entries

First usable sector is 34, last usable sector is 976773134

Partitions will be aligned on 8-sector boundaries

Total free space is 141 sectors (70.5 KiB)

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

1 40 409639 200.0 MiB EF00 EFI system partition

2 409640 196206695 93.4 GiB AF00 Customer

3 196206696 197476231 619.9 MiB AB00 Recovery HD

4 197476352 976773119 371.6 GiB 0700 BOOTCAMP

5 976773120 976773119 0 bytes 0700 DOWNLOAD 1

Also using the "NTFS start and size in your table" - are you referring to 197476352 and 779296768? I doubt there is any room for error, hence seeking clarification.

Will wait for confirmation before proceeding.

Thanks again.

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Answer 9

Loner T

Level 9

59,471 points

Jul 2, 2015 4:06 AM in response to Pom_VZ

We are not deleting any data content on the disk. The goal is to create a partition entry which reflects the appropriate Bootcamp partition. The d and n commands in Gdisk delete the partition markers, not the actual data.

Notice, in the linked article, there is a '+' sign in step 8, which is called offset notation. Instead of specifying absolute sector addresses, the second entry specifies a size that should be added to the first number when calculating the end sector address. Either notation is valid, but the '+' value is a size, which two other utilities use, GPT and Fdisk. Gdisk uses start/end. It is much easier to understand that the number in MBR, GPT and what is being entered are the same.

The steps will look like

Install GPT Fdisk (aka gdisk). You need to use the following steps. If you see any error messages during the following steps, please stop and post back here with the error message. The following steps have values from your MBR output (and you can verify) in Steps 7 and 8. Please notice the '+' sign in step 8 (this is called offset notation). The text in parentheses is for informational purpose to describe the action being taken. Gdisk has one-character commands except when entering numbers.

Rebuild GPT4 using start/end offsets

Sudo gdisk /dev/rdisk0
P (print the full list of parts)
D (delete)
4 (part 4)
D (delete)
5 (part 5)
N (new part)
4 (part 4)
197476352 ( - Start offset in bytes or the start point for Bootcamp part)
+4097488896 ( - Size offset, as opposed to End offset)
0700 (Windows part type)
P (print list of all parts just to see what changes will be made)
W (Write the new GPT)
Y (Yes! really write the new GPT)

This will delete and re-write the GPT partition information for /dev/disk0s4.

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Answer 10

Pom_VZ Author

Level 1

0 points

Jul 2, 2015 4:26 AM in response to Loner T

Really appreciate the help.

I'm 1/2 way through and have a slight conflict. All went well up to step 10. My disk went from asking for the start offset in step 9 (entered OK) and then step 10 asks for a last sector and not an offset.

It appears to have rejected the +4097488896 value and has asked again. Is the suggested value 976773134 acceptable?

Disk /dev/rdisk0: 5860533168 sectors, 2.7 TiB

Logical sector size: 512 bytes

Disk identifier (GUID): 00000E82-4754-0000-7204-0000CB700000

Partition table holds up to 128 entries

First usable sector is 34, last usable sector is 976773134

Partitions will be aligned on 8-sector boundaries

Total free space is 141 sectors (70.5 KiB)

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

1 40 409639 200.0 MiB EF00 EFI system partition

2 409640 196206695 93.4 GiB AF00 Customer

3 196206696 197476231 619.9 MiB AB00 Recovery HD

4 197476352 976773119 371.6 GiB 0700 BOOTCAMP

5 976773120 976773119 0 bytes 0700 DOWNLOAD 1

Command (? for help): d

Partition number (1-5): 4

Command (? for help): d

Partition number (1-5): 5

Command (? for help): n

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

First sector (34-976773134, default = 197476232) or {+-}size{KMGTP}: 197476352

Last sector (197476352-976773134, default = 976773134) or {+-}size{KMGTP}: +4097488896

Last sector (197476352-976773134, default = 976773134) or {+-}size{KMGTP}:

Thanks,

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Answer 11

Loner T

Level 9

59,471 points

Jul 2, 2015 4:45 AM in response to Pom_VZ

Pom_VZ wrote:

Disk /dev/rdisk0: 5860533168 sectors, 2.7 TiB

First usable sector is 34, last usable sector is 976773134

These two lines conflict. The two highlighted numbers show two different sizes of your disk. What tools were used to move the 500Gb partition to the 3Tb disk?

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Answer 12

Pom_VZ Author

Level 1

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Jul 2, 2015 4:59 AM in response to Loner T

Relying on memory here, but after the 500g was taken out and the 3tb fitted, I restored from a time machine backup leaving plenty of unallocated space.

The bootcamp setup gave me a size partition that it wanted for 2nd OS, and after realising that I couldn't get my 3tb, just went with it.

After the windows installation, windows let me resize the window partition to utilise some of the wasted space, but still not the whole 3tb. This was a while ago, and I mucked around to try and get access to as much of the drive as I could. (Probably where the two sizes for that partition come from. The Bootcamp size and the size Windows let me expand it to.)

Would this be easier if I ripped the drive out, and repaired it using Partition Magic or the like? (assuming I can hobble together a Windows box)

Cheers,

(PS - Off line for a while now)

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