Windows Upgrade Help and more

+1 Yeah, and after that, you'll likely need to enable Secure Boot in the BIOS too—that's probably the "S" error.

Same here. I had the same problem on my ASUS board. I had to go into the BIOS and switch from "Other OS" to "Windows UEFI Mode" for Secure Boot to actually initialize properly. Hope that helps.

You could also try a clean install from a USB drive instead of the upgrade path, as that sometimes bypasses weird detection problems. Hope that helps.