Ubuntu apt-get update 403 Forbidden

After running apt-get update, today I obtained a lot of 403 errors in the command log.

W: Failed to fetch http://ro.archive.ubuntu.com/ubuntu/dists/precise-backports/restricted/binary-amd64/Packages  403  Forbidden
W: Failed to fetch http://ro.archive.ubuntu.com/ubuntu/dists/precise-backports/universe/binary-amd64/Packages  403  Forbidden
W: Failed to fetch http://ro.archive.ubuntu.com/ubuntu/dists/precise-backports/multiverse/binary-amd64/Packages  403  Forbidden
W: Failed to fetch http://ro.archive.ubuntu.com/ubuntu/dists/precise-backports/main/binary-i386/Packages  403  Forbidden
W: Failed to fetch http://ro.archive.ubuntu.com/ubuntu/dists/precise-backports/restricted/binary-i386/Packages  403  Forbidden
W: Failed to fetch http://ro.archive.ubuntu.com/ubuntu/dists/precise-backports/universe/binary-i386/Packages  403  Forbidden
W: Failed to fetch http://ro.archive.ubuntu.com/ubuntu/dists/precise-backports/multiverse/binary-i386/Packages  403  Forbidden

Lucky me, one of my friends got this before me and already had the fix.

sudo apt-cache clean
sudo apt-get clean
cd /var/lib/apt
sudo rm -Rf lists.old/lists
sudo mv lists lists.old
sudo mkdir -p lists/partial
sudo apt-get clean
sudo apt-get update
sudo apt-get upgrade