Every time I have installed Koha I have had to fix this. After symlinking the koha-httpd.conf file to the apache/sites-enabled I have to add directory access for /usr/local/koha/opac/htdocs and /usr/local/koha/intranet/htdocs. This is not in the install file for ubuntu and it seems like it is a bug. the complete fix for me was to add: <Directory "/usr/local/koha/opac/htdocs"> Options Indexes FollowSymLinks AllowOverride None Order allow,deny Allow from all </Directory> to the Virtualhost on *:80 and to add: <Directory "/usr/local/koha/intranet/htdocs"> Options Indexes FollowSymLinks AllowOverride None Order allow,deny Allow from all </Directory> to the virtual host on *:8080
I submitted this when I first started working with Koha. I was mistaken in my setup.