Boot Camp Windows 7 "Missing Operating System"

Question

Level 1

4 points

Boot Camp Windows 7 "Missing Operating System"

Hello everyone,

I have been using my macbook pro with OSX and windows 7 (installed via bootcamp) for years and everything has been fine.

Recently I partitioned my MacBook Pro (Retina, late 2013, 500 GB) to install Ubuntu (I suppose some called it triple boot). After a while Ubuntu actually works fine (that partition is in ext4 format). To my surprise it is the windows partition that does not work anymore, returning the error message "Operating System Not Found".

From my understanding it is a fairly common error for anyone that partitioned their Mac that uses dual boot. I believe there are posts with similar issue and I tried to follow the post "Repairing Boot Camp after creating new partition" and saw the following commands as a solution:

setpid 4

07

flag 4

p

write

y

I couldn't understand what do they do and hence I DID NOT try it.

Here I am going to post all the screen shots that provide relevant details and hopefully someone could help me.

The partition:

*The 60 (59.22) GB "Untitiled" partition is Ubuntu

$ diskutil list

* Which, fairly clear disk05 (150 GB) is my windows 7 partition. (disk04 should be Ubuntu)

$ sudo gpt -r -vv show disk0

$ sudo fdisk /dev/disk0

* not sure what the * on the left / right mean

PS. The windows partition seems all intact. I can access it in OSX, I just cannot boot it.

PSS. If you would kindly, please explain a bit about your solutions (for me and the others)

PSSS. I do use rEFind to boot up now, but I don't think it matter. I also tried to press alt/ option when boot up, choose windows HD, also returning "Missing Operating System".

PSSSS.

$ sudo gdisk /dev/disk0

returned "sudo: gdisk: command not found" , will check that out if the information is required

Thanks a lot.

Mac Pro, iOS 10.2.1

Posted on Jan 23, 2017 5:33 PM

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Answer 1

Loner T

Level 9

59,536 points

Jan 30, 2017 2:50 AM in response to D Sean

GPT Fdisk provides gdisk command - https://sourceforge.net/projects/gptfdisk/ .

Since you now have an additional partition, you intend to keep, please see [Help] Can't boot to windows (8.1) after resizing partition for reference. You need to use the Gdisk steps to rebuild your MBR. Be aware that this MBR can break, so good backups are paramount.

If you are unsure, please ask questions.

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Answer 2

D Sean Author

Level 1

4 points

Jan 23, 2017 8:34 PM in response to Loner T

Hi, thanks for the quick reply.

Just tried the command

sudo gdisk /dev/disk0:

I will try your solutions in that post later on today, (both Part A and B- with 14 steps).

Is there anything else I should pay attention to?

Thanks

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Answer 3

D Sean Author

Level 1

4 points

Jan 30, 2017 2:50 AM in response to Loner T

Sorry for my late reply, I followed your instructions and it works well.

Here are some screen shots I took during the process, especially for the flagging part, in case anyone need it as a reference.

* interesting, two of them are called "default 07"

Thanks a lot.

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Answer 4

Loner T

Level 9

59,536 points

Jan 30, 2017 7:58 AM in response to D Sean

Excellent. Please back up OS X, Windows and create a Windows System Restore point.

D Sean wrote:

* interesting, two of them are called "default 07"

You have two MS Data entries. Are they causing issues? In this configuration, you cannot read the OS X partition anymore. This is a 'compromise' in order to get the extra partition working.

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Answer 5

Loner T

Level 9

59,536 points

Jan 23, 2017 9:13 PM in response to D Sean

Look at the Q&A and set the proper boot flags. The 14 steps are repeatable as many times as you need them. After you verify booting of Windows, remember to re-enable SIP with csrutil enable.

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