Create Deploy USB Memory task fails in error C1420127

Summary

When Create Deploy USB Memory task does not successfully complete or is forcefully terminated, since DISM image is not unmounted, create Deploy USB Memory task fails in error.
When this error occurs, please unmount the mounted image.

Workaround

1) Close the entire Windows Explorer.

2) Start command prompt with administrator authority.

3) Run the following command and monitor the mount status

DISM /Get-MountedImageInfo

C:\WINDOWS\system32> dism /get-mountedimageinfo

Deploy Image service and Image Management Tool
Version : 10.0.20348.1

Mounted Image: 

Mount Directory: C:\Windows\Temp\ADK10_amd64\mount
Image File: C:\Windows\Temp\ADK10_amd64\media\sources\boot.wim
Image Index: 1
Mount as Read-only / Writable: Yes
Status: OK

The task normally completed.

4) Run the following command and unmount the image.

DISM /Unmount-Wim

C:\WINDOWS\system32> dism /Unmount-Wim /MountDir:C:\Windows\Temp\ADK10_amd64\mount /discard

Target Product

- ActiveImage Deploy USB 4