Something is really screwed up with this image.

Booting from an USB installation image indicates that it's already part way through an upgrade ???, and to remove the install media, then select 'yes', which then just boots back to the 0xc000021a error.

I've now pulled out the drive and dropped it into a caddie attached to a laptop and then ran DISM from there, and not referring to the source image. Also crashes as 88.1%:

C:\WINDOWS\system32>DISM /Image:\ /Cleanup-Image /RestoreHealth

Deployment Image Servicing and Management tool
Version: 10.0.15063.0

Image Version: 10.0.15063.0

[===========================88.1%=================== ]
Error: 0x800f081f

The source files could not be found.
Use the "Source" option to specify the location of the files that are required to restore the feature. For more information on specifying a source location, see

The DISM log file can be found at C:\WINDOWS\Logs\DISM\dism.log

How do I get DISM to pull from MS Online sources ?
- At least I've now got decent access to the logs... see below.

Checking System Update Readiness.

(p) CBS MUM Corrupt Microsoft-Windows-TestRoot-and-FlightSigning-Package~31bf3856ad364e35~amd64~~10.0.15063.0
(p) CBS MUM Corrupt Microsoft-Windows-TestRoot-and-FlightSigning-WOW64-Package~31bf3856ad364e35~amd64~~10.0.15063.0
(p) CSI Manifest Corrupt
Repair failed: Missing replacement manifest.
(p) CSI Payload Corrupt amd64_netfx35cdf-cdf_wf_target_files_31bf3856ad364e35_10.0.15063.0_none_7d772a48a9714995\Workflow.VisualBasic.Targets
Repair failed: Missing replacement payload.
(p) CSI Payload Corrupt amd64_microsoft-windows-audio-audiocore_31bf3856ad364e35_10.0.15063.250_none_0ba66eff4afb95b7\AUDIOKSE.dll
Repair failed: Missing replacement payload.
(p) CSI Payload Corrupt x86_microsoft-windows-d..gement-winproviders_31bf3856ad364e35_10.0.15063.250_none_f035c8ec52ea8472\OSProvider.dll
Repair failed: Missing replacement payload.
(p) CSI Payload Corrupt amd64_netfx-vb_compiler_ui_b03f5f7f11d50a3a_10.0.15063.0_none_0ce3ec56326f7269\vbc7ui.dll
Repair failed: Missing replacement payload.
(p) CSI Payload Corrupt amd64_microsoft-windows-wmi-core_31bf3856ad364e35_10.0.15063.0_none_ca67dc4e5867595b\NCProv.dll
Repair failed: Missing replacement payload.

The 'FlightSigning' files are not a problem, as I removed them manually, but have backups I can put back in place.

Surely if I can get DISM to pull from the online source, it should fix them ?