do-release-upgrade -c

gksudo gedit /etc/update-manager/release-upgrades

sudo apt-get update
do-release-upgrade -c

sudo apt-get install ppa-purge
sudo ppa-purge ppa-name

sudo apt-get update

sudo apt-get --purge autoremove
sudo apt-get clean all
sudo apt-get purge $(dpkg -l | awk '/^rc/ { print $2 }')

sudo do-release-upgrade

sudo apt-get update
sudo do-release-upgrade

sudo software-properties-gtk

sudo apt-get update

do-release-upgrade -d

sudo apt-get upgrade

sudo apt-get dist-upgrade

sudo sed -i 's/quantal/saucy/g' /etc/apt/sources.list /etc/apt/sources.list.d/*.list

sudo apt-get update        # here's where you might get some errors you can ignore.
sudo apt-get dist-upgrade  # point of no return

sudo apt-get update

sudo apt-get dist-upgrade

sudo do-release-upgrade