I'm trying to upgrade 12.04 to 12.10 using a startup disk, but when I am supposed to choose the type of installation I want, Upgrade option is not available. Can anybody help? I don't want to use Update manager.
I created a USB startup disk from ISO and booted using that to upgrade my 11.10 installation. But when I am not able to select Upgrade from Ubuntu 11.10 to Ubuntu 12.04. The radio button cannot be selected. I am doing a Network upgrade now.