How to upgrade from 11.10 to 12.04?

Question

I am using 11.10 and I really want to update to 12.04 but it's impossible. I cannot see it in the update manager (I did select the option for the releases). I tried sudo update-manager d, and sudo-apt get upgrade and sudo apt-get upgrade release d but nothing. And sudo do-release-upgrade is not working as well! (I get "no release found" message.)

So finally I did put on a live USB and when I boot, I click on install, then it's telling me that I do have 11.10 and I can select for erase all and install Ubuntu 12.04 or I can install along 11.10 and the second option to update 11.10 to 12.04 is grey. I cannot selected it! Why? Am I running out of options?

What else can I do to upgrade to 12.04?

Answer 1

Try this:

sudo sed -i 's/lts/normal/g' /etc/update-manager/release-upgrades; sudo do-release-upgrade

Answer 2

I have 11.04 as well, my teacher told us to write this on the terminal:

sudo do-release-upgrade

in about 5 minutes select yes and it will let you upgrade. This may take some hours and leave it there until it is finished.