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Related question: Why does integrity check fail for the 12.04.1 Alternate ISO?

I downloaded and wrote ubuntu-12.04.3-server-amd64.iso to a USB key, but when I boot from it and select "Check disc for defects", I get the error: "The ./boot/grub/efi.img file failed the MD5 checksum verification..."

I'm using OS X, so the steps for writing the ISO to the USB key are as follows:

hdiutil convert -format UDRW -o ubuntu-12.04.3-server-amd64.img ubuntu-12.04.3-server-amd64.iso
sudo dd if=ubuntu-12.04.3-server-amd64.img.dmg of=/dev/rdisk1 bs=1M
diskutil eject /dev/disk1

The MD5 for the ubuntu-12.04.3-server-amd64.iso is OK, md5 ubuntu-12.04.3-server-amd64.iso gives MD5 (ubuntu-12.04.3-server-amd64.iso) = 2cbe868812a871242cdcdd8f2fd6feb9 which is the same as the MD5 on the Ubuntu website.

Is this the same issue as the question linked above? Can I proceed OK?

share|improve this question
Where is the ./goot/ coming from? Or did you mean ./boot/? – Thomas W. Jan 11 '14 at 19:17
@ThomasW. corrected, thanks. – Douglas B. Staple Jan 11 '14 at 20:46
What happens if you skip the convert process and try dd the iso directly? Do you get the same result? – Elder Geek Apr 14 '15 at 14:56

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