Khalil Majdalawi's Blog

If you are seeing Ubuntu GPG Error BADSIG use the one of the following methods to fix

Error Message:
W: GPG error: http://archive.canonical.com intrepid Release: The following signatures were invalid: BADSIG 40976EAF437D05B5 Ubuntu Archive Automatic Signing Key

Try to run the following commands from terminal

sudo -i
apt-get clean
cd /var/lib/apt
mv lists lists.old
mkdir -p lists/partial
apt-get clean
apt-get update

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