There is no particular cause that has been found for this issue, but we do have some potential workaround and fix this error. We will be discussing them all in this article.
Windows Upgrade error 0xa0000400
We will be discussing the following fixes to get rid of error 0xa0000400 for Windows 11/10 Upgrades:
1] Use Disk Cleanup
Some residual junk system files like Cache files and driver residue can block an upgrade. Hence, I would recommend you to run Disk Cleanup to delete the files and data that is safe to be removed from your computer. The main files that you need to remove here should be Previous Windows Installations. You can also use third-party software like CCleaner to clean up System and Registry junk that might be causing a conflict.
2] Get the official ISO files
The best way to upgrade to Windows 11/10 without encountering this error would be to get the official ISO files for Windows 111/0’s latest release. And then you can use this ISO to upgrade to the latest version of Windows 11/10.
3] Turn off the Internet connections at a specific time
This workaround is tricky. What you can do is, when the update is downloaded using the upgrade tool that you are using, you can just disconnect the Internet connection.
This is fine because all the files needed would be already downloaded safely and the tool will now only be responsible for installing the newer updates using those files.
4] Get a newer version of Media Creation Tool
You can also get and use the latest version of the Media Creation Tool and check if that fixes your issues.
5] Run Windows Update Troubleshooter
You can also try to fix this issue by running the Windows Update troubleshooter. Did these fixes help you?
