Went to install bootcamp on Late 2012 iMac with 3TB fusion drive. Went through the Boot Camp setup as I have many times before. Got to Windows setup just before you select the drive. Clicked on Partition 4 BOOT CAMP - went FORMAT - tried to hit NEXT, would not go. The message was something like 'Windows cannot be installed to this disk, ensure that disk's controller is enabled in the bios menu.' Apparently the problem was that I had the optical drive plugged in via USB as well as a USB hub and the setup doesn't like that. I was installing Windows with a bootable USB made with Boot Camp assistant. So I unplugged all but the bootable and restarted. Couldn't get back into setup. It said press any key to boot from and nothing happened. Went back to OS X, to Boot Camp assistant to remove Windows 7 and I get this. Your disk could not be restored to a single partition. Went to Disk Utility to remove Windows 7, which was actually 750gb FAT 32 partition. Partition it to OS X journaled. Now I have a partition called '14' formatted Mac OS X Journaled. I cannot delete it or merge it with my main partition again. So now I have like 2TB OS X and this stupid 750 OS X partition. I am beyond annoyed right now. I want to merge this back into one partition and restart the Boot Camp process. Need this fixed by tomorrow.