Volume to volume cloned Windows not booting up

I’ve done a volume to volume clone from a source internal SSD bootcamp volume, to an external USB 3.0 windows volume.

Trying to boot Windows 10 from this external volume, the computer tries three times (i.e. reboots itself, after showing the rotating balls animation for some minutes), then gives up with this error on a blue screen:

    "Your PC couldn't start properly.
     After multiple tries, the operating system on your PC failed to start, 
     so it needs to be repaired.
     Error code: 0xc00000001
     You'll need to use recovery tools on your installation media.... etc. etc."

On this forum, I’ve read the proposed workaround for this problem: to restore from an image. Alright, I’m trying that now, but also getting nowhere… I’ve made an image of the bootcamp Windows installation, storing it on the internal SSD. From that I’ve used Winclone’s restore feature to restore to the external USB. That process now appears stuck, with the progress bar at about 15%… and it’s been at that 15% for a couple of hours.

Any tips would be greatly appreciated!


Edit: I should add that I’m running Winclone 7.3.4 on a Macbook Pro (late 2013) under MacOS 10.13.6 High Sierra, with the Bootcamp partition on the internal 1TB SSD, and the (attempted) clones on external USB3 4TB HDD.

Update: the system restore from an image did complete overnight. (I don’t understand why restoring a <50Gb partition should take so long). The results are no different with this system “restored” from an image - just like my system cloned “volume to volume” - I cannot boot the laptop from the external HDD. I am now researching/learning about “dual boot” PCs, where I am getting into stuff that is way over my head. Could it be that windows in general cannot easily be booted off of an external HDD, when there is a windows volume on the internal drive?

This is all completely alien to me. I’ve been using Macintosh since the late 1980’s and it has always been trivial to choose your boot volume, and boot from there. (edit) I am not yet an experienced user of Windows.

My goal is still very simple: I want to test my external “clone” of Windows-10, to see that it will run the laptop in case the internal drive fails (or is corrupted, or is “held for ransom” by a ransomware attack, etc.). I can’t figure out a way to do it.

0xc00000001 is inaccessible file
image or SSD is damaged or Windows’s USB driver cannot read it
but I am not sure