Unable to install Windows 8.1 via Boot Camp

Question

Level 1

4 points

Unable to install Windows 8.1 via Boot Camp

Hi!

Firstly, i apologize because of my English.

I have searched all questions and answers about "We couldn't create a new partition or locate an existing one" and i have been trying all recommendations since a month. After all sleepless nights i have gain nothing.

My problem is this: I had installed Windows 8.1 via Boot Camp and i was working fine. I tried to upgrade it Windows 10 according to windows instructions and it's done. But my drivers did not work. I tried to install latest Boot Camp drivers, but it didn't work. The i decided to uninstall Windows 10 via Boot Camp and achieved it. Later, i wanted to install Windows 8.1 again. But as you guess it fails: "We couldn't create a new partition or locate an existing one."

I have iMac 27 late 2013 with 1 TB fusion drive. I tried to delete logical volumes, create again, merge etc. Every time, i got this error. I am not familiar with terminal but anyway i tried. Even tried ta separate fusion drive and install OS X Yosemite on only SSD and install Windows on only HDD. But i didn't work again. Once i completely destroy fusion drive and let Disk Utility to restore it (that red message and fixing after it). Nothing did help.

I want to install Windows 8.1 via Boot Camp again.

I have bootable OS X Yosemite USB flash drive (so, i am volunteer to do your advices)

I also have bootable WINISTALL USB flash drive that created by Boot Camp.

I now use OS X El Capitan GM Candidate on my iMac.

PLEASE HELP ME. THANK YOU.

My diskutil cs list is:

and my diskutil list is:

Disk Utility:

iMac, OS X Yosemite (10.10.5)

Posted on Sep 10, 2015 6:11 PM

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Answer 1

Loner T

Level 9

59,471 points

Sep 11, 2015 7:20 AM in response to kalebend

1. ELC GM will cause problems. Please use Yosemite.

2. Your Mac supports both modes of installation, Legacy BIOS/MBR or EFI Boot. Which method(s) have you used on Yosemite?

3. If you use BCA and let it partition and install W8.1 without interrupting using Alt/Option key, where does the installation fail?

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Answer 2

kalebend Author

Level 1

4 points

Sep 11, 2015 9:21 AM in response to Loner T

I can turn to Yosemite. It is not problem.

I have used both method. First, i used BOOTCAMP partition and Window normal installation. It failed.

Then, i use EFI... it failed again.

- Bootcamp create the partition and windows installation starts.. I choose language etc. Then, continue..

After i format bootcamp partition (which is 4. partition of disk 1 not disk0).. it fails and i get this:

"We couldn't create a new partition or locate an existing one"

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Answer 3

Loner T

Level 9

59,471 points

Sep 11, 2015 9:34 AM in response to kalebend

1. For EFI, since you already have the USB installer, use BCA and remove any BC/Windows partitions. Run Disk Utility, create a Free Space partition (which will on your HDD) and use the USB to boot from and point to this Free Space. It will be split into MSR and MSD parts by the installer.

2. For normal Legacy Boot, use BCA only. Run DU Repair Disk. Boot in Safe Mode and then boot normally and try BCA again. Safe Mode is detailed in Try safe mode if your Mac doesn't finish starting up - Apple Support .

Do not mix the two methods.

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Answer 4

kalebend Author

Level 1

4 points

Sep 11, 2015 9:38 AM in response to Loner T

I want to ask this:

Is this diskutil list normal for installation. Why windows can't create a new partition? What causes this? Is my fusion drive ok?

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Answer 5

kalebend Author

Level 1

4 points

Sep 11, 2015 10:39 AM in response to kalebend

I did repair disk via DU.

Boot in safe mode, then, boot normally.

Try BCA again.

Result (step by step)

,

Please help me.

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Answer 6

Loner T

Level 9

59,471 points

Sep 11, 2015 12:45 PM in response to kalebend

Leave it in this state and switch to OSX. Please post the output of

sudo gpt -vv -r show /dev/disk1

sudo fdisk /dev/disk1

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Answer 7

kalebend Author

Level 1

4 points

Sep 11, 2015 2:35 PM in response to Loner T

I leaved it that state and switch to OS X Yosemite.

Output of sudo gpt -vv -r show /dev/disk1:

Output of sudo fdisk /dev/disk1:

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Answer 8

Loner T

Level 9

59,471 points

Sep 11, 2015 6:54 PM in response to kalebend

Download GPT Fdisk (http://sourceforge.net/projects/gptfdisk/).

Rebuild MBR to match the new GPT information thus resetting the Hybrid MBR. Use defaults for other questions (like partition codes). The only values that need modifications are the Boot flags and step 10. Accept all other defaults that Gdisk offers. Please see thesample Q&A as an example. These steps can be repeated if you make a mistake before you get to Step 12, otherwise start from Step 1 for these steps. Step 6 has numbers which are typed with a space between the numbers. Please see the sample Q&A before you execute these steps.

Sudo gdisk /dev/rdisk0
P (Print list of parts)
R (Recover)
O (print current Hybrid MBR)
H (chooses Hybrid)
Partitions numbers to be hybridized: 2 3 4
Y (Good for GRUB question)
N (part 2 boot flag)
N (part 3 boot flag)
N (part 4 boot flag)
O (print current Hybrid MBR)
W (Write the new MBR)
Y (Yes! write the new MBR)
Reboot

Here is sample Q&A for this section. Please notice the Press Enter/Return.

Place EFI GPT (0xEE) partition first in MBR (good for GRUB)? (Y/N): Y

Creating entry for GPT partition #2 (MBR partition #2)

Enter an MBR hex code (default AF): Press Enter/Return

Set the bootable flag? (Y/N): N

Creating entry for GPT partition #3 (MBR partition #3)

Enter an MBR hex code (default AB): Press Enter/Return

Set the bootable flag? (Y/N): N

Creating entry for GPT partition #4 (MBR partition #4)

Enter an MBR hex code (default 07): Press Enter/Return

Set the bootable flag? (Y/N): Y

After you have completed these steps, try to install Windows

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Answer 9

kalebend Author

Level 1

4 points

Sep 11, 2015 3:47 PM in response to Loner T

i got this at the end of the process: (different from yours)

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Answer 10

Loner T

Level 9

59,471 points

Sep 11, 2015 6:54 PM in response to kalebend

Say 'N' and then q to quit from Gdisk. Step 1 should be sudo gdisk /dev/rdisk1 since you have a Fusion drive and the Bootcamp partition is on the HDD part of the Fusion disk.

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