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I have two HDDs in my iMac (OS 10.7.5 - Lion) both of which are partitioned as "Mac OS Extended (Journaled)" (according to Disk Utility).

Here's the two drives:

df -l -h
Filesystem     Size   Used  Avail Capacity  Mounted on
/dev/disk0s2  107Gi   50Gi   57Gi    48%    /
/dev/disk0s4  190Gi   34Gi  156Gi    19%    /Volumes/Macintosh HD 2

I started up Bootcamp in order to install Windows 8 to the 2nd Harddrive (which I don't think has the OS installed - though I'm not sure or how to find out if it is).

Bootcamp then throws an error saying:

**The startup disk cannot be partitioned or restored to a single partition.**
The startup disk must be formatted as a single Mac OS Extended (Journaled) volume or already partitioned by Boot Camp Assistant for installing Windows

Furthermore the option "Install or remove Windows 7" is disabled.

I'm a Mac newbie (I come from the Windows world), so I'm not sure what this is about. All I want to do is leave the primary (and only) partition on disk0s2 and add a Win8 partition to disk0s4.

What do I need to do?

share|improve this question
I'm reasonably sure you only have a single physical hard drive, and that it is already partitioned... which would explain the error. – Bon Gart Sep 8 '13 at 22:34
I'm not too familiar with the Boot Camp tools per se, but you could try using Disk Utility to adjust the size of your second partition (/dev/disk0s4) and create a third for Windows. If you create it as FAT, it will probably create a hybrid MBR, which should then enable you to install Windows. DO NOT re-partition the disk using the Windows installer, though; just install straight to the FAT partition that the Windows installer should see. – Rod Smith Sep 9 '13 at 4:05

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