Most of the Windows Insiders seems facing this error, when upgrading to the new 20H1 build 18875. Eventhough, Microsoft acknowledged that, this is a known issue on one of the post, one of our fellow insider has found the solution to the error 0xca00a000 while upgrading to 20H1 build 18875.
What Microsoft Says,
We have received feedback from some Insiders that they are seeing a 0xca00a000 download error for Build 18875. We are investigating. Please upvote feedback item https://aka.ms/AA4qqb2 if you have experienced this issue.
So, What is the solution ?
The solution is really simple, you need to disable Windows search service, before the upgrade process that's it.
It might look weird, but It was found to be working for most of our fellow folks, so give it a try.
How to do it?
1) Press Windows and R Keys, which will display Run command.
2) Type services.msc on the box.
3) Scroll down, to Windows search service, and disable the service.
4) Restart your PC
and try again, it will work.
Hope it helps.
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Error 0xca00a000 while upgrading to 20H1 build 18875 [Solution]
4/ 5Oleh Logesh