While Updating to 2021-03 Cumulative Update Preview for windows 10 version 21H1 for x64-based systems ( KB5000842 )
The following error is displaying
Download Error – 0x800f081f
Kindly resolve it at your earliest
Regards ,
Bhargava B U
Hi, I have solved the same problem following this link
https://www.yourwindowsguide.com/2020/10/cannot-initiate-repair-install-windows-10-20h2.html
you need to change the owner of a registrty key following the option 4 from this link
good luck