Select the Troubleshoot option, select Advanced options, and then select UEFI Settings. Your computer will restart into the advanced boot options screen. To do this, open the Settings charm - press Windows Key + I to open it - click the Power button, then press and hold the Shift key as you click Restart.

To access this screen, you’ll need to access the boot options menu in Windows 8. You can control Secure Boot from your UEFI Firmware Settings screen. See the last section for instructions on booting from a removable device. You should be able to install current versions of Ubuntu - either the LTS release or the latest release - without any trouble on most new PCs. If you need to boot an older Linux distribution that doesn’t provide any information about this, you’ll just need to disable Secure Boot. You should check to see which process your Linux distribution of choice recommends. This doesn’t seem to be a common at the moment.

Add a Signing Key to the UEFI Firmware: Some Linux distributions may sign their boot loaders with their own key, which you can add to your UEFI firmware.

This is also necessary if you want to install an older version of Windows that wasn’t developed with Secure Boot in mind, such as Windows 7.

Disable Secure Boot: Secure Boot can be disabled, which will exchange its security benefits for the ability to have your PC boot anything, just as older PCs with the traditional BIOS do.

Users may have to disable Secure Boot to to use Ubuntu on some PCs. However, a Ubuntu developer notes that Ubuntu’s boot loader isn’t signed with a key that’s required by Microsoft’s certification process, but simply a key Microsoft says is “recommended.” This means that Ubuntu may not boot on all UEFI PCs. This is because Ubuntu’s first-stage EFI boot loader is signed by Microsoft.

Choose a Linux Distribution That Supports Secure Boot: Modern versions of Ubuntu - starting with Ubuntu 12.04.2 LTS and 12.10 - will boot and install normally on most PCs with Secure Boot enabled.

You have several options for installing Linux on a PC with Secure Boot: Organizations could use their own keys to ensure only approved Linux operating systems could boot, for example. You can choose to disable it or even add your own signing key. On an Intel x86 PC (not ARM PCs), you have control over Secure Boot. Secure Boot blocks this - the computer will only boot trusted software, so malicious boot loaders won’t be able to infect the system.

Disable secure boot asus uefi