the update for ubuntu 12.04 appeared in my update manager, I started the update but I had to stop it. Now, I'm still with the 11.10 version and the update don't appear in my manager. How do I update now, without downloading a new disc version?
That's simple, go to Update Manager, press Settings, then at the bottom of window, infront of Notify me of a new Ubuntu version, Select For any new version then that 12.04 LTS Upgrade Message appears.
Hope it helps.
try this. This will update your resources list and update your current packages.
then run this
to upgrade your system to the latest version of ubuntu