Upgraded to Mojave from El Captain and now Windows 10 Boot Camp is missing OS?

Question

Upgraded to Mojave from El Captain and now Windows 10 Boot Camp is missing OS?

I have the latest October update of Windows 10 installed on my MacBook Pro (late 2013). I decided it was time to update from El Captain to Mojave. When I went to switch back to Windows after the update using the Restart while holding option method. My Windows partition did not show up.

Back in Mojave I checked disk utilities and this is what I saw:

I had no access to my Windows 10 files in Finder at all.

Next I checked diskutil list in Terminal:

Note /dev/disk2 is a windows 10 recovery USB I was using, so please ignore. I can see my Microsoft Basic Data 179GB is on dev/disk0

I then continued with this fix: https://discussions.apple.com/thread/7682561?answerId=30728111022#30728111022

basically disabled SIP and then entered these commands in Terminal:

sudo fdisk -e /dev/disk0

p

setpid 4

07

flag 4

p

w

y

upon reboot with Option key held I saw a windows drive option. When I select it I get the "Missing Operating System" Error.

My next course of action was to attempt to fix the windows startup with a boot disk. The fix startup failed. I opened command prompt and attempted a chkdsk /F, but that fails becuase the disk is locked. I then tried to activate the partition with diskpart but that fails to make a difference either. So I went back to Mojave and am now reaching out to the community for help. Below are my results for the Terminal commands:

diskutil cs list

sudo gpt -vv -r show /dev/disk0

sudo fdisk /dev/disk0

Please help.

Thank you

MacBook Pro 15", 10.14

Posted on Feb 18, 2019 8:32 PM

Reply

Answer 1

Loner T

Level 9

59,536 points

Feb 22, 2019 4:30 PM in response to CaptainZCarnage

If you notice, your Start address - 423694336 - is in the range where GPT3 - 423693560 - is located. You need to delete GPT3 and GPT4, both.

You need to run

d

3

d

4

before you can use the Start address.

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Answer 2

Loner T

Level 9

59,536 points

Feb 19, 2019 4:24 PM in response to CaptainZCarnage

Step 1 - Convert disk0s3 to free space. Run the following command only once, otherwise you will lose data

diskutil eraseVolume free free disk0s3

Reboot and post the output of

diskutil list

before we go further.

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Answer 3

Loner T

Level 9

59,536 points

Feb 20, 2019 6:15 AM in response to CaptainZCarnage

Resizing with third-party tools leaves old NTFS headers which cause problems during macOS upgrades.

Can you look at El Capitan has deleted my bootcamp window… - Apple Community as an example of Testdisk usage? It shows the screen flow. Please ask questions, before you run Testdisk, if something is not clear.

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Answer 4

Loner T

Level 9

59,536 points

Feb 19, 2019 7:44 PM in response to CaptainZCarnage

The current Windows partition isn't showing up at all. I can't even access it in finder.

This is not a good sign. It may not show up in boot manager, but it should show up in Finder as a NTFS partition.

I'm fine with adding the empty space to the macOS side but either way I think the MBR needs help.

Before we build the MBR, we need to locate the 'correct' NTFS header. Before the Mojave upgrade, has the Windows partition been resized in the past, using any tools?

Are you familiar with Testdisk?

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Answer 5

Loner T

Level 9

59,536 points

Feb 22, 2019 5:09 PM in response to CaptainZCarnage

Since we do not GPT4, you will hybridize 2 3 and mark 3 with a 'Y' for boot-ability.

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Answer 6

Loner T

Level 9

59,536 points

Feb 22, 2019 5:32 PM in response to CaptainZCarnage

Type 'n' and continue.

Sorry I think I'm almost done bugging you. I appreciate the help, I'm in completely foreign territory.

No worries. Ask as many questions as want to.

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Answer 7

Feb 19, 2019 6:26 AM in response to Loner T

Thank you for the reply LonerT.

I assume this means I need to absorb Disk0s3 by expanding either my Mojave or my Windows 10 partition, then go back through the steps to correct the MBR, and re-enable the SIP. If this is the case do you have a link to a good resource for the steps I need to follow. I will be searching the forums and Google but if you have something I would appreciate it. I have resized partitions before on this device but it has been a few years and I do not recall the steps required.

Thank you

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Answer 8

Loner T

Level 9

59,536 points

Feb 19, 2019 6:50 PM in response to CaptainZCarnage

If the current Windows disk space is not causing any issues, it is easier to absorb it into the APFS (macOS) side. If you decide to merge it into Windows, it requires Windows Startup Repair after GParted partition work.

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Answer 9

Feb 22, 2019 5:44 PM in response to Loner T

And with that my world is back in order and the mac boots faster than ever. I re-enabled SIP and am backing up and creating a restore point.

I know you get thank yous a lot but i had extremely important stuff on the windows side and decided to update stupidly without backing up. I never do that. So you really saved my backend. I wish i could do more than just say thank you.

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Answer 10

Feb 19, 2019 4:55 PM in response to Loner T

Done.

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Answer 11

Loner T

Level 9

59,536 points

Feb 19, 2019 6:17 PM in response to CaptainZCarnage

What you do want to do with the current disk0s3?

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Answer 12

Feb 19, 2019 6:28 PM in response to Loner T

It can be added to either the windows or mac side partition. Whichever is easier. I just want my windows side to work again.

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Answer 13

Feb 19, 2019 7:10 PM in response to Loner T

The current Windows partition isn't showing up at all. I can't even access it in finder. I'm fine with adding the empty space to the macOS side but either way I think the MBR needs help.

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Answer 14

Feb 22, 2019 4:39 PM in response to Loner T

Then new 3 or new 4? since I'm deleting 3 I'd assume the next command to be :

N

3

but I want to be sure.

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Answer 15

Loner T

Level 9

59,536 points

Feb 22, 2019 4:47 PM in response to CaptainZCarnage

Yes, it should be N 3.

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Upgraded to Mojave from El Captain and now Windows 10 Boot Camp is missing OS?

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