I was following http://bleeptobleep.blogspot.com/2013/02/mac-install-windows-7-or-8-on-external.html and successfully installed Windows 8.1 on a WD Element 2TB USB 3.0, without any issue. However, since the performance was really poor to run Win8.1 on that WD Element, I purchased aLaCie Little big Thunderbolt 512GB (256GB * 2 RAID), I formated the two Disk as simple NTFS format (i.e. RAID not enabled), and deployed Win8.1 installation and enabled bcdboot on the first disk, the processes were: imagex.exe /info C:\wim\install.wim imagex.exe /apply C:\wim\install.wim 1 o: o:\windows\system32\bcdboot o:\windows /f ALL /s b: So b: is the MBR primary section (500MB), and o: is a partition (60GB) on the thunderbolt disk 1 (256GB). However, after rebooting from my iMac, while I tried to start the normal Win8.1 installation, I saw the Win8 BCD boot error: 0xc000000e, basically it prompts me that "Your PC Needs to be Repaired", displayed 9 options by pressing F8 key, I tried each one of them but no one even worked... I really need help at this point, appreciate for any help!