# UEFI boot doesn't work in Rocky 9.3 installer using mkksiso **URL:** \ **Category:** Rocky Linux Help & Support\ **Created:** [February 5, 2024, 10:36pm UTC](https://forums.rockylinux.org/t/uefi-boot-doesnt-work-in-rocky-9-3-installer-using-mkksiso/12764 "2024-02-05T22:36:03Z")\ **Posts on this page:** 1\ **Showing post:** 2
**Author:** ![gerry666uk](https://avatars.discourse-cdn.com/v4/letter/g/dbc845/32.png) [@gerry666uk](https://forums.rockylinux.org/u/gerry666uk)\ **Post date:** [February 8, 2024, 7:22pm UTC](https://forums.rockylinux.org/t/uefi-boot-doesnt-work-in-rocky-9-3-installer-using-mkksiso/12764/2 "2024-02-08T19:22:41Z")
See also my recent post: > [@Can't install from Rocky boot media, and BOOTX64.EFI](https://forums.rockylinux.org/t/cant-install-from-rocky-boot-media-and-bootx64-efi/12642): > > A friend has a PC, ASUS Z97M-PLUS, happily running CentOS 8.x. It was originally installed in UEFI mode (with secure boot) using media ‘CentOS-8-x86\_64-1905-dvd1.iso’. I want to install Rocky (8 or 9), but it fails straight away with the error: Invalid image Failed to read header: Unsupported Failed to load image: Unsupported start\_image() returned Unsupported I know this is partly to do with the EFI firmware being old, but I think it’s also to do with the “shim”, BOOTX64.EFI. The Fedora … --- _[View the full topic](https://forums.rockylinux.org/t/uefi-boot-doesnt-work-in-rocky-9-3-installer-using-mkksiso/12764)._