USB Bootcamp: INACCESSIBLE_BOOT_DEVICE i'm on a late 2012 iMac (15C50) and created a Windows 10 Bootcamp installation which worked fine. I transferred it to a external USB SSD with Winclone 5 which basically worked. I can still select it as a boot target in system settings and it starts to boot. While booting i get a blue screen with INACCESSIBLE_BOOT_DEVICE Error.

Does anyone know of a chance to get that fixed? I can boot into recovery mode sometimes (Recovery with network works most of the time). But normal boot definitely fails every time with the same error.

Is this probably a general incompatibility from my external drive case (I tried two from Inateck) with EFI Boot procedure or am i just missing some Windows drivers?

Any hint is appreciated.
You need to go into regedit and change the registry hardware config / boot driver flag to a 14 hex value before you clone the drive to the external usb drive.  Watch this video it will show you how to do it live https://www.youtube.com/watch?v=9RHjVAQHb3E