How to fix the Ubuntu GPG Error BADSIG

[zero-n]

If you have got this error:


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


when you try to use:


apt-get update

then there is two methods to fix this :


Method 1:
Run these commands one after another:


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


Method 2:
Run these commands one after another:


sudo aptitude -o Acquire::http::No-Cache=True -o Acquire::BrokenProxy=true update

sudo apt-get update


Thanks to ubuntu-geek (http://www.ubuntugeek.com/how-to-fix-the-ubuntu-gpg-error-badsig.html)