Q: Repairing Boot Camp after creating new partition

I'm running OS X 10.9 and Windows 7 x64 Pro.

I set up Boot Camp to dual-boot Windows on my MacBook Pro Retina. Everything was fine. And just yesterday Apple released the Yosemite Beta for the public and I wanted to download this and give it a try. After some research, I found that creating a separate partition was the way to go, and so I made another partition.

I wasn't aware that this would affect my Windows partition as I thought it was completely different.

So now, when I boot up, there is no option to boot with Windows. But when I boot the Mac and select Startup Disk, it shows Boot Camp is still there and all my files etc are still there.

I have a 256SSD, 160GB was for the Mac, and I have 90GB set for Windows.

I made the new partition to 40GB (and the Mac was now 120GB).

Then once I completed that part, I restarted my Mac and the Windows boot option was no longer there.

I didn't even install the Yosemite yet. I went to Disk Utility and deleted the 40GB partition that I made.

Now I don't know what to do. I have a lot of important things which are still on my Windows. Is there a way to restore normal Boot Camp functionality?

MacBook Pro (Retina, 13-inch, Late 2013), OS X Mavericks (10.9.4)

Posted on Jul 25, 2014 8:20 AM

I have this question too

Solved

Loner T

Level 7 (23,898 points)

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sudo fdisk -e /dev/disk0

setpid 4

flag 4

write

Now Reboot and hold the ALT key and check if Windows shows up and is bootable.

If you get 'missing operating system', then Windows Startup Repair and see if Windows will comeback alive.

If you notice the difference between the Disk Utility screen (two partitions) vs the fdisk output (or the GPT) there are 'hidden' partitions and the MBR partitioning style used for Windows allows a maximum of 4 partitions. If you need further explanation, read the original thread.

Yosemite should not be installed on any machine that is critical to you. If only partitioning was done, but Yosemite was NOT installed, you are in better shape. Yosemite ignores and is unaware of bootcamp and creates an additional Recovery HD and moves things around.

Posted on Jul 25, 2014 9:04 AM

Q: Repairing Boot Camp after creating new partition

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by Loner T,

Loner T Jul 30, 2014 6:54 PM in response to joaomalveiro
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Jul 30, 2014 6:54 PM in response to joaomalveiro

Please start a new thread and post a reference here. Your configuration will not work the way it is.

Please post the output of

1. sudo fdisk /dev/disk0
2. sudo gpt -vv -r show /dev/disk0
3. sudo dd if=/dev/rdisk0s6 count=1 2>/dev/null | hexdump -C

In the current setup, you have three choices,

1. Create a new hybrid MBR, which is fragile, and can break if you do any software upgrades or remove Yosemite.
2. Use an EFI Windows which is fully supported in Windows 8/8.1 on Late 2013 and newer hardware.
3. Use a second internal/external disk to install Yosemite.

Bootcamp use a MBR, so any disk which has more than 4 partitions, will not work for non-EFI bootcamp.
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by maccing,

maccing Aug 6, 2014 5:05 PM in response to MacTavish_10
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Aug 6, 2014 5:05 PM in response to MacTavish_10

thank u 'loner t', u r a life safer, hope u are in good position in life by your knowledge.
I tried above method and achieved, but at last stage when i power cycled and tried to boot into windows then under score starts blinking continuously. then no further process starts at all-like windows logo appears...etc.
i am using 500gb,macbook pro, mid 2012, windows 8.1(bootcamp).
can anyone please help?!
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by Loner T,

Loner T Aug 6, 2014 5:24 PM in response to maccing
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Aug 6, 2014 5:24 PM in response to maccing

Please start a new thread an post a reference here. If you can put the output of the four commands in this thread in the new thread, that would be wonderful.
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by maccing,

maccing Aug 6, 2014 6:56 PM in response to MacTavish_10
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Aug 6, 2014 6:56 PM in response to MacTavish_10

repairing partition after installing Yosemite beta to other partition
to loner T
thank u for ur time
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by maccing,

maccing Aug 6, 2014 7:08 PM in response to MacTavish_10
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Aug 6, 2014 7:08 PM in response to MacTavish_10

i am not able to create new thread ( really sorry tried many times),
i dont understand how to know the name of drive in which boot camp is created, it shows as "bootcamp"
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by Loner T,

Loner T Aug 6, 2014 7:30 PM in response to maccing
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Aug 6, 2014 7:30 PM in response to maccing

1. Please remove any personal information, including your name, if you do not want it to be visible in a public forum.
2. Your thread may get removed due to reference to Yosemite.
3. This configuration is going to be painful, since you have a single disk system. I suggest removing the coming-in-fall OS and putting it on an external drive, if available. You will need a fast drive.
4. Let me look at the other thread.
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by Loner T,

Loner T Aug 7, 2014 3:44 AM in response to maccing
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Aug 7, 2014 3:44 AM in response to maccing

Please remove references and create a new thread. I cannot access your old thread.
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by maccing,

maccing Aug 7, 2014 5:30 AM in response to Loner T
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Aug 7, 2014 5:30 AM in response to Loner T

i am sorry for the delay, i have no internet connection outside my house
my new thread solving bootcamp problems after partition
hope this works
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by maccing,

maccing Aug 7, 2014 5:38 AM in response to MacTavish_10
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Aug 7, 2014 5:38 AM in response to MacTavish_10

solving bootcamp problems after partition
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by joaomalveiro,

joaomalveiro Sep 22, 2014 7:33 PM in response to Loner T
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Sep 22, 2014 7:33 PM in response to Loner T

Ok i decided to delete all the partitions and only keep Mavericks. Now the problem is when i turn on my Mac it will always try to boot from a non-existent windows partition. How can i solve this?

Using the following menu i don't have any other options beside the Mavericks. I don't understand why it keeps trying to boot from windows, i've to hold Alt key every time.
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by Loner T,

Loner T Sep 22, 2014 7:57 PM in response to joaomalveiro
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Sep 22, 2014 7:57 PM in response to joaomalveiro

Did you use Bootcamp Assistant to remove Windows or was the partition removed via Disk Utility.
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by joaomalveiro,

joaomalveiro Sep 23, 2014 1:38 AM in response to Loner T
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Sep 23, 2014 1:38 AM in response to Loner T

i did it using disk utility, didn't occur to me that would be tool to uninstall it
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by Loner T,

Loner T Sep 23, 2014 4:10 AM in response to joaomalveiro
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Sep 23, 2014 4:10 AM in response to joaomalveiro

You need to remove the MBR entries that have Windows. Check the output of sudo disk /dev/disk0.
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by joaomalveiro,

joaomalveiro Sep 23, 2014 4:21 AM in response to Loner T
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Sep 23, 2014 4:21 AM in response to Loner T

that command doesn't work :/

jcmm@jcmm ⭕ ~ sudo disk /dev/disk0.
sudo: disk: command not found
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by Loner T,

Loner T Sep 23, 2014 5:23 AM in response to joaomalveiro
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Sep 23, 2014 5:23 AM in response to joaomalveiro

Try sudo fdisk /dev/disk0. (Safari auto-corrected fdisk to disk ).
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