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I am following these instructions to create a Bootable USB Drive for me Mac and this is the output I get on step 8.

new-host:~ Jason$ sudo dd if=/Users/Jason/Desktop/ubuntu-12.04-desktop-amd64.dmg of=/dev/rdisk1s2 bs=1m
dd: /dev/rdisk1s2: Invalid argument
691+1 records in
691+0 records out
724566016 bytes transferred in 164.544659 secs (4403461 bytes/sec)

What should I do?

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Have you unmounted the USB stick with `unmountDisk /dev/rdisk1s2' before running the command to write to the USB? It's very important that this is done before running that. – lordqwerty Feb 1 '13 at 13:58

You should use unetbootin it is SO MUCH EASIER just reformat your disk and then throw the iso onto the flashdrive using unetbootin.

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Dang! I might take a look at that. I made a 12.04 Live-USB for my Macbook 1.2, late 2007. It helped to have a working Live-CD so I could check Linux names for the USB stick, and so on. I used the instructions at for making a Live-CD, but had to burn the disk 4-5 times before I got one that worked reliably.

I could NOT make a Live-USB following the directions at They may work for newer Macbooks, but not mine. I found a link to these instructions. Then I messed around with the grub.cfg file for days before I got:

# grub.cfg for MB1,2 USB Install F11

# Timeout for menu



menuentry "UBUNTU USB" {

       echo "FAKEBIOS"

       echo "SET ROOT"

       #set prefix=(hd1,2)/boot/grub
       #set root=(hd0,1)

       set root=(hd1,2)

       #set root=(hd1,2)/boot/grub 

       #echo "INSMOD"
       #insmod (hd1,2)/boot/grub/linux.mod

       echo "LINUX"
       linux /vmlinuz root=/dev/sdb2 video=efifb agp=off

       echo "INITRD"
       initrd /initrd.img

       echo "IMPLIED BOOT"

I found the echos very helpful. It gets all the way up to the implied boot and almost finishs, but failed mounting things on root, like /dev on /root/dev. I played around with the 'root=' arg on the linux command until hit on the one that there. I left a bunch of other stuff in comments. They didn't work for me, but they might for you.

I didn't find much out there. I even found a claim the Macbooks can't boot from a USB stick. I hope this helps.

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