Bootcamp / We couldn't create... / can't return to Windows installation

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Barbatian Author

Level 1

6 points

Bootcamp / We couldn't create... / can't return to Windows installation

Hello,

I used Bootcamp to install Windows 10. I have iMac late 2015, so I do have my Win 10 iso. image on my hard drive.

Bootcamp took it from hard drive and proceeded with actions. It restarted to windows.

I received error: "We couldn't create a new partition or locate an existing one".

I followed apple instruction:

Now I can't back to installation. I see bootcamp partition, however I do not have it as startup disk anywhere - system preferences nor while restarting mac with option key. Any ideas?

Bootcamp assistant want only to merge partitions back. I do not want to lose couple of hours again for bootcamp assistant downloading again support files.

Kind regards,

Michal

iMac (Retina 5K, 27-inch, Late 2015), macOS Sierra (10.12)

Posted on Oct 1, 2016 12:48 PM

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Answer 1

Loner T

Level 9

59,536 points

Oct 1, 2016 7:56 PM in response to Barbatian

Please see If you see a partition alert while using Boot Camp to install Windows - Apple Support .

Disconnect all external storage, and run SMC and NVRAM reset

Reset the System Management Controller (SMC) on your Mac - Apple Support

How to Reset NVRAM on your Mac - Apple Support

Late 2015 Macs do not use a USB Installer, and the Windows ISO must be on the internal OS X drive, not on an external disk. The steps for installing Windows are documented in https://help.apple.com/bootcamp/assistant/6.0/#/bcmp173b3bf2 .

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Answer 2

Oct 29, 2016 9:53 AM in response to Loner T

I too repeatedly encountered the very same error after reinstalling Windows 10 (version 1607) with Boot Camp Assistant 6.1.0 in macOS 10.12.1 on the 3TB Fusion Drive of my iMac (Retina 5K, 27-inch, Late 2015).

The steps suggested by Apple in their support article were insufficient to solve the problem until I followed your suggestions to reset the SMC and the NVRAM on my iMac.

One or the other (or both) of those suggestions made the difference, and I've now successfully installed the Windows 10 Anniversary Edition. (I'm cloning my Boot Camp partition as I write this.)

Thank you very much indeed, Loner T!

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Answer 3

Loner T

Level 9

59,536 points

Oct 29, 2016 10:09 AM in response to Community User

Excellent. Please remember to backup OS X, Windows and create a Windows System Restore point.

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