When You Already Have A Bootable ISO
Recovery and installation tools are often supplied as prepared ISO images. Use an image from the publisher you trust and check any checksum supplied with it. The image itself must support the computer and boot method you intend to use.
Choose Image File in Burn / Write, select the ISO and write it to suitable blank media. This route preserves the boot structure already present in the image.
When You Are Building Your Own Image
Build Image includes a Boot Image (El Torito) section. It provides a Create bootable disc option and fields for the boot image, emulation mode and platform. These are authoring settings for a known boot image, not a way to turn arbitrary files into a working operating system.
Use the boot-image instructions supplied by its creator. BIOS and EFI boot requirements differ, and guessing a boot image or platform can produce a disc that is readable as data but cannot start the target computer.
A Practical Boot-Disc Check
- Identify whether the source is a complete bootable ISO or a separate boot-image component.
- Select the matching image-writing or image-building workflow.
- Write to media the computer can read and check the recorded contents.
- Use the computer boot menu to select the optical drive.
- Confirm that the expected recovery or installer screen appears before relying on the disc.
Keep A Recovery Disc Ready To Use
Label the disc with its purpose and supported system, and retain the source image separately. A successful burn message cannot confirm that the firmware will boot it; testing on the intended machine is the useful final check.