"An operating system wasn't found"

Support
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Welcome to the forum! :slight_smile:

Three questions…

  1. Is the firmware ─ be it BIOS or UEFI ─ effectively set to boot from the optical drive or the USB drive?

  2. Are you sure you created the bootable medium in the correct manner? The .iso file must be imaged to an optical disk or a USB stick, not copied to it as a file.

  3. Is your computer a 64-bit machine? Manjaro no longer supports 32-bit hardware.