Q: Difficulty installing windows in imac via Boot Camp

Hi. I'm trying to install Windows 10 to an iMac (Retina 5K, 27-inch, Late 2014) via the Boot Camp Assistant (BCA), but having difficulty.

I've created the windows startup disk via BCA to a USB 3.0 drive. After the partition is setup via BCA, Windows Installer launches. I follow the instructions from the support articles, which state to select the BOOTCAMP partition (in this case Drive 0 Partition 4) and click Format.

After I click Format, I get a message that states "We couldn't create a new partition or location an existing one. For more information, see the Setup log files."

I tried to search the computer and the USB drive for setup.log files to no avail.

Please help!

iMac with Retina 5K display, OS X Yosemite (10.10.5)

Posted on Oct 9, 2015 7:42 PM

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Q: Difficulty installing windows in imac via Boot Camp

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by Loner T,Helpful

Loner T Oct 9, 2015 8:43 PM in response to Minboo71
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Safari

Oct 9, 2015 8:43 PM in response to Minboo71

1. You need to use a good reliable brand of USB2 flash drive. USB3 drives can create problems. USB hard disks should not be used.
2. The error message is related to external storage in most cases - Boot Camp: "We couldn't create a new partition or locate an existing one" alert during Windows 8 install - Apple Support .
3. Disconnect all external storage, USB hubs, external hard disks and try again.
4. There could be other issues, but try these steps first.
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by Minboo71,

Minboo71 Oct 9, 2015 8:45 PM in response to Loner T
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Oct 9, 2015 8:45 PM in response to Loner T

Thank you! I thought everything was disconnected (it's my parent's iMac)... but Time Machine was still connected. Once I disconnected Time Machine, I was able to complete the installation.

So far, I've been able to boot to both Windows and OS X. Now just to figure out how to switch back and forth. Back to the support pages I go!

Thanks again...
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by Loner T,

Loner T Oct 9, 2015 8:53 PM in response to Minboo71
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Oct 9, 2015 8:53 PM in response to Minboo71

Please see Boot Camp: Set the default operating system .

OSX -> Windows - Use System Preferences -> Startup Disk -> select BC/Windows and Restart.
Windows -> OSX - Use Control Panel -> System -> Boot Camp -> select OS X and Restart. You can also use the System Tray.
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by Minboo71,

Minboo71 Oct 12, 2015 8:41 AM in response to Minboo71
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Oct 12, 2015 8:41 AM in response to Minboo71

thank you! i was hoping to be able to swap without restarting but I understand the theory as to why restarts are necessary.

Thank you so much for your assistance!
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Q: Difficulty installing windows in imac via Boot Camp

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by Loner T,★Helpful

by Minboo71,

by Loner T,

by Minboo71,

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by Loner T,Helpful