I upgraded to Ubuntu 12.04 (from 11.10) this morning. After the installation succeeded, the computer restarted and since then I have not been able to use my keyboard or mouse (once I get to the graphical UI login screen).
Is it possible to rollback the installation to its previous state? I am hoping to avoid a fresh install as I have installed a bunch of dev tools and its quite painful to have to re-install everything
[EDIT] : Title changed. The previous title was "How to rollback Ubuntu installation to 64bit 11.10" as installing Ubuntu 12.04 over 11.10 ended up making my computer unusable