Bootcamp problem(s) after partition

Question

Level 1

8 points

Bootcamp problem(s) after partition

Hello there,

Got into a bootcamp problem after partition, with no bootcamp icon visible at start-up, partitioned again to get to original state and after spending the last weekend reading Loner T’s remedies for other guys tried (probably stupidly) the ”p, setpid 4, 7, flag 4, p, w, y” as frustration grew. Now I have the bootcamp icon appearing in alt-option of boot drive selection but when I select it, I get ”no bootable disk – insert boot disk…”. To me this is looks a bit like maccing’s problem here: discussions.apple.com/thread/6483998. If you Loner T are around, could you help me with this? The optimal solution for me would be to have 150GB for bootcamp (i.e. 100 GB larger than originally) but if that is out of question, I’m also very happy to have it as it is at 50GB (which it has been since the start) as long as I get old windows with old data running. If nothing can be done, that would be info as well so that I know to start from scratch…I’m just a ”regular user" and by no means a ”root level” guy but willing to put effort into this to get it sorted out and would be very grateful for any help.

My iMac is 21.5 inch, Mid 2011 with mac OS High Sierra (10.13.6) and with Windows 7

In case someone is willing to try to help me here are my current diskutil list

/dev/disk0 (internal, physical):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *500.1 GB disk0

1: EFI EFI 209.7 MB disk0s1

2: Apple_HFS Macintosh HD 450.0 GB disk0s2

3: Apple_Boot Recovery HD 650.0 MB disk0s3

4: Microsoft Basic Data BOOTCAMP 49.2 GB disk0s4

gpt

gpt show: /dev/disk0: mediasize=500107862016; sectorsize=512; blocks=976773168

gpt show: /dev/disk0: Suspicious MBR at sector 0

gpt show: /dev/disk0: Malformed MBR at sector 0

gpt show: /dev/disk0: Pri GPT at sector 1

gpt show: /dev/disk0: Sec GPT at sector 976773167

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 878907576 2 GPT part - 48465300-0000-11AA-AA11-00306543ECAC

879317216 1269536 3 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC

880586752 96186368 4 GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7

976773120 15

976773135 32 Sec GPT table

976773167 1 Sec GPT header

fdisk

Disk: /dev/disk0 geometry: 60801/255/63 [976773168 sectors]

Signature: 0xAA55

Starting Ending

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

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

1: EE 1023 254 63 - 1023 254 63 [ 1 - 976773167] <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: 07 0 0 0 - 0 0 0 [ 0 - 0] HPFS/QNX/AUX

Posted on Mar 8, 2021 12:21 AM

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Answer 1

Loner T

Level 9

59,477 points

Mar 8, 2021 6:45 AM in response to juki21

This looks like a valid NTFS header. Do you have GPT Fdisk (https://sourceforge.net/projects/gptfdisk/)? If not, can you install it? Once installed, we can correct MBR using the following steps.

Rebuild MBR to match the new GPT information thus resetting the Hybrid MBR. Use defaults for other questions (like partition codes). The only values that need modifications are the Boot flags and step 10. Accept all other defaults that Gdisk offers. Please see the sample Q&A as an example. These steps can be repeated if you make a mistake before you get to Step 12, otherwise start from Step 1 for these steps. Step 6 has numbers which are typed with a space between the numbers. Please see the sample Q&A before you execute these steps.

Sudo gdisk /dev/rdisk0
P (Print list of parts)
R (Recover)
O (print current Hybrid MBR)
H (chooses Hybrid)
Partitions numbers to be hybridized: 2 3 4
Y (Good for GRUB question)
N (part 2 boot flag)
N (part 3 boot flag)
Y (part 4 boot flag make NTFS bootable partition)
O (print current Hybrid MBR)
W (Write the new MBR)
Y (Yes! write the new MBR)
Reboot

Here is sample Q&A for this section. Please notice the Press Enter/Return.

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

Creating entry for GPT partition #2 (MBR partition #2)

Enter an MBR hex code (default AF): Press Enter/Return

Set the bootable flag? (Y/N): N

Creating entry for GPT partition #3 (MBR partition #3)

Enter an MBR hex code (default AB): Press Enter/Return

Set the bootable flag? (Y/N): N

Creating entry for GPT partition #4 (MBR partition #4)

Enter an MBR hex code (default 07): Press Enter/Return

Set the bootable flag? (Y/N): Y

Test 1 - Does Bootcamp Volume show up in Finder?

Test 2 - Can you see files in Bootcamp Volume?

Test 3 - Can you select Bootcamp in System Preferences -> Startup Disk?

Test 4 - If Test 3 is successful, select Bootcamp and Click Restart.

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Answer 2

juki21 Author

Level 1

8 points

Mar 8, 2021 6:32 AM in response to Loner T

Thanks very much for picking this up and bearing with me, hear we go:

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 b0 7c 34 |........?.....|4|

00000020 00 00 00 00 80 00 80 00 ff af bb 05 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 67 b5 91 9a d4 91 9a 92 |........g.......|

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 70 0e 16 68 09 00 66 53 66 53 66 |h...hp..h..fSfSf|

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

00000110 28 10 b9 d8 0f fc f3 aa e9 5f 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 a0 f8 01 e8 09 00 |...u...fa.......|

00000170 a0 fb 01 e8 03 00 f4 eb fd b4 01 8b f0 ac 3c 00 |..............<.|

00000180 74 09 b4 0e bb 07 00 cd 10 eb f2 c3 0d 0a 41 20 |t.............A |

00000190 64 69 73 6b 20 72 65 61 64 20 65 72 72 6f 72 20 |disk read error |

000001a0 6f 63 63 75 72 72 65 64 00 0d 0a 42 4f 4f 54 4d |occurred...BOOTM|

000001b0 47 52 20 69 73 20 6d 69 73 73 69 6e 67 00 0d 0a |GR is missing...|

000001c0 42 4f 4f 54 4d 47 52 20 69 73 20 63 6f 6d 70 72 |BOOTMGR is compr|

000001d0 65 73 73 65 64 00 0d 0a 50 72 65 73 73 20 43 74 |essed...Press Ct|

000001e0 72 6c 2b 41 6c 74 2b 44 65 6c 20 74 6f 20 72 65 |rl+Alt+Del to re|

000001f0 73 74 61 72 74 0d 0a 00 8c a9 be d6 00 00 55 aa |start.........U.|

00000200

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Answer 3

juki21 Author

Level 1

8 points

Mar 8, 2021 8:07 AM in response to juki21

Works like a charm, kudos to you, I owe you more than the proverbial beer! As a final question (and to avoid what happened here) - is it in your view correct to assume that the only safe way to increase the bootcamp partition means deleting windows and reinstalling it using bootcamp assistant for the whole process or can third party sw do this better/more easily (and if this is the case any particular sw to consider) ? Thank you so much one more time.

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Answer 4

juki21 Author

Level 1

8 points

Mar 8, 2021 11:00 PM in response to Loner T

Great, thanks for the comment and all the help. Once again, things get done and are often less complicated when you know what you’re doing...

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Answer 5

Loner T

Level 9

59,477 points

Mar 8, 2021 2:51 PM in response to juki21

I use Winclone for this but you can also try CloneZilla. Also, if neither is a viable option, you can also look at Bootcamp Partition Missing after Resize - Apple Community.

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Answer 6

Loner T

Level 9

59,477 points

Mar 8, 2021 6:11 AM in response to juki21

Post the output of

sudo dd if=/dev/rdisk0s4 count=1 2>/dev/null | hexdump -C
The MBR is incorrect. Once we can check the output of the previous command, we can correct the issue(s).

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