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I am following the procedure from This Page

I have a 2012 macbook pro 13 inch and I am using a PNY 8gb flash drive. I have downloaded version 12.10 and already converted it into a .img file. My computer automatically puts a .dmg at the end of the file.

The problem comes when I execute step 8. Terminal runs the command and tells me it was successful, but immediately after, a window pops up saying my USB drive is "not readable by this computer"

This is what I type into Terminal.

sudo dd if=/Users/Trev_Carlson/Downloads/ubuntu-12.10-desktop-amd64.img.dmg of=/dev/disk2 bs=1m

Then it tells me to enter my password, I do, and it executes the command.

Is there anything I am doing wrong? Is the .dmg at the end messing it up? Also what format should the USB drive be if I want to use it to boot on my mac?

Thanks in advance!

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Yes, having the files as a .dmg rather than a .img is the problem. You converted your file to a be named "ubuntu-12.10-desktop-amd64.img.dmg" which is a .dmg file because it's last in line, even though .img is in the name.

Step 8 in the guide you're using says: "sudo dd if=/path/to/downloaded.img of=/dev/rdiskN bs=1m" Notice "downloaded.img" and how it's not "downloaded.img.dmg" like you have it. Make sure you typed everything in step 3 correctly, it should be "sudo hdiutil convert -format UDRW -o /Users/Trev_Carlson/Downloads/ubuntu-12.10-desktop-amd64.img /Users/Trev_Carlson/Downloads/ubuntu-12.10-desktop-amd64.iso"

If that's still not working, I would suggest looking at this guide from the page instead: Step 4 in the guide says "Note: OS X tends to put the .dmg ending on the output file automatically." What this step is saying that OS X tries to make it a .dmg file unless you force it to make it a .img file instead.

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You are doing everything correctly! That is the way that it is supposed to be. Just eject and put into any computer you need. It always works for me that way.

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