Corrupt SQL Server 2014 Express Installation - Unable to Uninstall/Re-install

On Windows 10, I've uninstalled a corrupt installation of the above, but when I try to reinstall, I keep getting errors. The uninstall has left folders and files behind in both the Program Files and Program Files (x86) folders. I've used CCleaner to tidy up the registry, but still getting errors, the latest of which is:

Error code 0x800F081F

I also did a system restore, but the folders and files are still present.

I went to MS support and got the following suggestion:

"To fix the error codes for Windows 10, follow these steps: Download the Windows Media Creation tool, and create an ISO image locally, or create an image for the version of Windows that you have installed."

Problem is, when I run this tool, it wants to completely reinstall Windows, instead of giving me the option to create a disc image.

Any ideas on how I can clean up the corrupt the SQL Server Express installation and start over?

Thanks in advance, Allan