Posted 23 June 2015 - 01:59 PM
You should be able to still use UEFI without secure without having to go to legacy BIOS mode. On most computers you have three basic choices for booting, and the settings for them are in different places in the "UEFI settings" (found by holding shift and restarting, then going through "troubleshoot" and "advnaced options")interface depending on the hardware manufacturer. The ways you should probably be able to boot are: UEFI with secure boot, UEFI without secure boot, BIOS legacy without secure boot(secure boot cannot work under BIOS at all). On some machines you might only have the options of: UEFI with secure boot and BIOS without secure boot, but most machines will have all three. The setting to enable or disable secure boot will probably be in a different part of the interface than the setting for choosing between UEFI or legacy BIOS. You MIGHT be able to boot the disc you are talking about by using the "UEFI without secure boot" way of booting, and then switching on secure boot at a later time once you have installed from the disc (I assume this is what you are trying to do, boot the disc and then install the OS from it), if you want secure boot to be active.
Back on this site, for a while anyway, been so busy the last year.
My systems:2 laptops, intel i3 processors, windows 8.1 installed on the hard-drive and linux mint 17.3 MATE installed to USB