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Repairing Boot Camp after creating new partition

Hi

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

Reply
180 replies

Jul 25, 2014 8:27 AM in response to MacTavish_10

Please post the output of


1. diskutil list

2. sudo fdisk /dev/<DiskWhereYouHaveInstalledBootcamp>

3. sudo gpt -v -r show /dev/<DiskWhereYouHaveInstalledBootcamp>


Bootcamp webpage clearly warns about this.


Yosemite also warns about installing on a backup mac. It also creates a hidden Recovery in addition to what you may already have for Mavericks.

Jul 25, 2014 9:04 AM in response to MacTavish_10

sudo fdisk -e /dev/disk0

p

setpid 4

07

flag 4

p

write

y


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.

Jul 25, 2014 9:39 AM in response to MacTavish_10

Please use fdisk not gdisk. 😉


Here is an example.


sudo fdisk -e /dev/disk0

Password:

fdisk: could not open MBR file /usr/standalone/i386/boot0: No such file or directory

Enter 'help' for information

fdisk: 1> p

Disk: /dev/disk0 geometry: 121643/255/63 [1954210120 sectors]

Offset: 0 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: AF 1023 254 63 - 1023 254 63 [ 409640 - 1452530904] HFS+

3: AB 1023 254 63 - 1023 254 63 [1452940544 - 1269536] Darwin Boot

*4: 07 1023 254 63 - 1023 254 63 [1454211072 - 499998720] HPFS/QNX/AUX

fdisk: 1> setpid 4

Starting Ending

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

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

*4: 07 1023 254 63 - 1023 254 63 [1454211072 - 499998720] HPFS/QNX/AUX

Partition id ('0' to disable) [0 - FF]: [7] (? for help)

fdisk: 1> flag 4

Partition 4 marked active.

Repairing Boot Camp after creating new partition

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