I was trying to install ubuntu using the instructions here: https://help.ubuntu.com/community/In...n/FromUSBStick

But when I select the drive in rEFIt, it displays this:
"No bootable device -- insert boot disk and press any key"
Some people have had this message appear after installing linux, but I am getting this message just from the installation media.

I couldn't get it to show up using a DVD/CD so I've turned to the flash drive. I've also tried holding the option key upon startup and it still does not work. It has done this for Ubuntu and Arch installations.

Any ideas?