Switching from Legacy to UEFI booting method
Switching from Legacy to UEFI booting method
You're encountering an issue with the OS partition not being found after following the guide. Let's try to clarify the steps and troubleshoot. Have you checked if the UEFI settings are correctly configured in your BIOS/UEFI? Also, ensure that the correct partition is selected during the boot process. If you're still facing problems, consider reinstalling the UEFI firmware or consulting the manufacturer's support resources.
Did you launch the terminal with administrative privileges? Please try accessing it in admin mode.