Lost my Win 10 partition after upgrading to macOS High Sierra

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Level 1

8 points

Lost my Win 10 partition after upgrading to macOS High Sierra

Hi!

I recently upgraded to macOS High Sierra (10.13.1) on my main Macintosh partition, and since then my Windows 10 partition does not show up anymore when I press the alt-key when booting. It now only shows the Mac partition instead of both.

Unfortunately I was so stupid and didn't do a back-up before upgrading, because I never encountered any problems before.

I found some similar questions here and apparently it is due to a switch to the APFS format, but I'm not an expert and really do not understand much about these things. I urgently need my Windows 10 partition, because I have software that I need for work on it. Is there any way to get it back without a clean install, considering that I didn't do a back-up before?

This is my system:

iMac Retina 5k 27", late 2014

4 GHz Intel Core i7

32 GB 1600 MHz DDR3

1 TB SSD drive and my partition split in bootcamp was 800 GB macOS / 200 GB Win 10

I really hope that I will not lose the data on my Windows 10 partition :/

Thanks in advance for any help or suggestions!

iMac with Retina 5K display, macOS High Sierra (10.13.1)

Posted on Nov 15, 2017 10:04 AM

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Answer 1

Vindobona Author

Level 1

8 points

Nov 18, 2017 4:34 AM in response to Loner T

If I have this information from EFI/GPT in Testdisk, do I still need to run Quick Search for the gdisk procedure that follows?

For some reason, Quick Search takes forever on my iMac. After 10 minutes it's not even 1% done.

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Answer 2

Vindobona Author

Level 1

8 points

Nov 18, 2017 7:13 AM in response to Loner T

When I return, I get this:

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

gpt show: /dev/disk0: mediasize=1000555581440; sectorsize=512; blocks=1954210120

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 1954210119

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 1565128664 2 GPT part - 7C3457EF-0000-11AA-AA11-00306543ECAC

1565538304 388671488 3 GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7

1954209792 295

1954210087 32 Sec GPT table

1954210119 1 Sec GPT header

sudo fdisk /dev/disk0:

Disk: /dev/disk0 geometry: 121643/255/63 [1954210120 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: FF 1023 254 63 - 1023 254 63 [ 409640 - 1565128664] Xenix BBT

3: 0C 1023 254 63 - 1023 254 63 [1565538304 - 388671488] Win95 FAT32L

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

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Answer 3

Vindobona Author

Level 1

8 points

Nov 22, 2017 10:06 AM in response to Loner T

The first 4 and the 6th MS Data entry give me a "Can't open filesystem. Filesystem seems damaged" message.

The 7th MS Data entry gives me a "No file found, filesystem may be damaged" message.

Only the 5th [Boot] and the 8th [EFISECTOR] MS Data entry show me something else, although they are very small:

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Answer 4

Loner T

Level 9

59,471 points

Nov 15, 2017 5:58 PM in response to Vindobona

You may need to temporarily disable SIP by booting into Local Recovery and running csrutil disable in Terminal. The header you have posted is not a valid NTFS header.

Can you use El Capitan has deleted my bootcamp windows partition as a reference an run Testdisk and run a scan?

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Answer 5

Vindobona Author

Level 1

8 points

Nov 15, 2017 1:46 PM in response to Loner T

diskutil list:

/dev/disk0 (internal, physical):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *1.0 TB disk0

1: EFI EFI 209.7 MB disk0s1

2: Apple_APFS Container disk1 801.3 GB disk0s2

3: Microsoft Basic Data 199.0 GB disk0s3

/dev/disk1 (synthesized):

#: TYPE NAME SIZE IDENTIFIER

0: APFS Container Scheme - +801.3 GB disk1

Physical Store disk0s2

1: APFS Volume Macintosh HD 513.9 GB disk1s1

2: APFS Volume Preboot 24.5 MB disk1s2

3: APFS Volume Recovery 520.8 MB disk1s3

4: APFS Volume VM 20.5 KB disk1s4

diskutil cs list:

No CoreStorage logical volume groups found

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Answer 6

Vindobona Author

Level 1

8 points

Nov 15, 2017 3:28 PM in response to Loner T

sudo dd if=/dev/rdisk0s3 count=1 2>/dev/null | hexdump -C:

00000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|

*

00000200

sudo fdisk /dev/disk0

fdisk: /dev/disk0: Operation not permitted

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Answer 7

Vindobona Author

Level 1

8 points

Nov 16, 2017 11:53 AM in response to Loner T

Thanks for your help so far. I'm entering completely unknown territory now but I'll try to do what you tell me step by step.

So I downloaded test disk 7.0 and when I started it, I got this message:

No disk found.

TestDisk will try to restart itself using the sudo command to get root (superuser) privileges.

I then entered my password and it tells me "No harddisk found".

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Answer 8

Loner T

Level 9

59,471 points

Nov 18, 2017 6:52 AM in response to Vindobona

This is the list of unrecoverable partitions. Press Return to Continue and you should see a viable list of partitions.

Can you post the output of

sudo gpt -vv -r show /dev/disk0

sudo fdisk /dev/disk0

If you get a permission error, then these can wait till the Testdisk search is finished and we need GPT Fdisk.

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Answer 9

Loner T

Level 9

59,471 points

Nov 18, 2017 7:30 AM in response to Vindobona

In the Testdisk screen, can you scroll down to the MS Data entry with Start at 1566461952 and use the 'p' command to list the directory contents? Post a screen shot. Do not use any other keys, till we confirm.

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Answer 10

Loner T

Level 9

59,471 points

Nov 22, 2017 11:11 AM in response to Vindobona

In Testdisk, the start of the MBR does not show up as a MS Data entry. This is why we do not see a valid NTFS header. Testdisk has also broken up the internal Boot and EFI Sectors, which is the second issue.

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Answer 11

Loner T

Level 9

59,471 points

Nov 22, 2017 1:31 PM in response to Vindobona

You may want to consider re-installing W10 on the existing partition, which should leave your non-OS files intact as long as you do not format the partition. Your current W10 installation should be moved to Windows.old.

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Answer 12

Vindobona Author

Level 1

8 points

Nov 22, 2017 1:31 PM in response to Loner T

Ok, thanks a lot for your help though. I don't know how to re-install it on that partition if the partition isn't even recognized, but I'll figure it out.

I have a back-up of my work-related data I think, but I really hope that I won't lose my 600+ hours worth of gaming achievements. For Steam games, maybe my progress is saved in some cloud anyway, I don't know much about these things.

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Answer 13

Loner T

Level 9

59,471 points

Nov 22, 2017 2:17 PM in response to Vindobona

A 2014 iMac should allow BC Assistant to create a USB Installer using the first two options - Create and Download. Use a USB2 flash drive. Once you have the USB installer, without using the Install option, boot from it using Alt/Option key, and select the existing partition as destination. You do not need to format, but Upgrade In-place.

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