It did for me.

I got tired of messing with it and refreshed mine also. Windows 10 installed without a glitch.

I may just have to try that if I can't get it any other way.

We couldn't find any search results in the Windows Store for "WindowsUpdate_dt000 OR C1420121"

When I check the update fail it says it failed with error code C1420121

I can't seem to find that error code to see what it actually is.

Same here setuperr.log 0 bytes

Not yet, I am still having the same issue.

Sorry I wasn't very clear.
I am trying to install from the dvd I created from the .iso file I obtained using the media creation tool.

Windows 10 installation fails at 18% with the message "Something went wrong" "windows 10 installation has failed"

I have made several attempts using using the .iso from the Windows 10 media...