[Koha] Koha OPAC site

Hi Guys! I have just finished installing Koha using this installation guide on *Ubuntu 12.04 LTS*. , http://wiki.koha-community.org/wiki/Koha_on_ubuntu_-_packages but the OPAC site does not work. It only displays this. It works! This is the default web page for this server. The web server software is running but no content has been added, yet. Could anyone suggest how I could get this fixed! Thanks! Richard