How to resolve 'unable to find a live file system' error during dual boot setup on old MacBook Air?

rauphelhunter wrote:

I was able to get into alternate boot by pressing Option/Alt key while power-on, hence select EFI-boot as media for OS which I intended to setup with for example - ubuntu 23.04

However until the step/screen where the setup just complained about "unable to find a medium containing a live file system"

Is this error while booting the Ubuntu installer? Or is it an error while booted to the installer & trying to select a destination drive for the installation? Much more detail is needed here.

Also, how did you create your bootable Ubuntu USB installer?

And what type of drive are you using? Some Linux installers must be using a standard USB stick which the OS sees as a USB stick and not a hard drive/SSD, otherwise you may have issues with the installer.

Are you trying to install Ubuntu to the internal SSD or an external drive?

Are you going to use the whole drive for Ubuntu or are you trying to use an existing partition to wipe?

If installing to an external drive, then I would connect the destination drive to the right USB port which is integrated into the Logic Board and use the left USB port for the installer. It really should not matter, but you never know & it could affect how it may fail.

Also why are you using such an old version of Ubuntu? Is that the most recent LTS version?

Also, I would not recommend using the default Ubuntu since it tends to be a resource hog & MBAirs are not known for having lots of resources. Choose one of the other flavors such as Kubuntu, or maybe use Linux Mint which is based on Ubuntu (uses different Desktop Environments although some overlap) instead which may perform a bit better on older systems plus Linux Mint is not using Snap containers by default which may also help as well.

Probably best to ask folks more knowledgeable in Ubuntu about that.

That seems to be an Ubuntu error:

• https://askubuntu.com/questions/15425/error-when-installing-unable-to-find-a-medium-containing-a-live-file-system#26864

The Utilities > Startup Security Utility app is applicable to T2, and not earlier (such as here):

About Startup Security Utility on a Mac with the Apple T2 Security Chip - Apple Support

Usual with macOS is probably running a guest with Ubuntu. Or maybe running macOS as a guest of Ubuntu, given you’re on Apple hardware. Dual boot usually works fine, but when it doesn’t the damage can be impressive.