Cannot get migrated Bootcamp partition to boot (Win 10)

Hi, I just installed and set up Bootcamp (Windows 10 Pro) on my 16-Inch MacBook Pro yesterday, and after getting it all set up, I purchased WinClone to migrate this over to an external disk, thus freeing up 100GB of space on my Macbook’s internal SSD.

I followed the instructions on the guide, but I cannot get windows to boot from the external disk. I cannot get past the various windows blue screens / Stop Codes.

I sometimes get the Recovery option, but when I attempt to boot in Safe mode or with boot logging, the same thing happens - Windows appears to be starting, but then the computer restarts, Apple Logo appears and it boosts into macOS.

I have tried the ‘Make EMI bootable’ option in WinClone.
I have not yet wiped the original BootCamp partition, incase something like this happened. I

Here’s what I’ve done:

I have partitioned a 256GB external SSD in USB 3 enclosure using Disk Utility to have 2 partitions, one MacOS volume, and a 100GB ExFAT partition (My Bootcamp partition is only 15GB, so should be plenty, as I’m only using windows for a very limited number of things)

It wasn’t allowing me to do a ‘volume to volume’ clone, so I performed a ‘Create Image from Volume’ on my BootCamp disk.

Once completed, I restored this image to the ExFat partition on my 256GB SSD.

When It failed to boot, including in safe mode, I relaunched WinClone and performed the ‘Make EFI bootable’ operation on the new External BootCamp (WinCloned) volume.

I have injected the AppleSSD driver onto the External BootCamp (WinCloned) volume, but it still will not boot.

I lost 5 hours yesterday trying to get this to boot.

When I start up the Mac holding the option key, the wincloned volume appears as “EFI”.

As I spent a while installing custom graphics drivers and other setting up, and considering that I am booting the migrated Win10 volume on the same computer, I didn’t think it was necessary to use ‘Sysprep’, as from what I read, it removed any custom drivers, which shouldn’t need removing.

Any help would be much appreciated,

Thanks,
Ryan

There have been reports that updating the Windows registry for MountedDevices helps resolve this issue. See here: