Change your sources.list to this:
by 
$sudo gedit /etc/apt/sources.list
then your password, off course


#
deb http://security.ubuntu.com/ubuntu/ hoary-security main restricted universe multiverse
#
deb http://archive.ubuntu.com/ubuntu/ hoary-updates main restricted universe multiverse
#
deb http://archive.ubuntu.com/ubuntu/ hoary main restricted universe multiverse
#
 
#
deb-src http://security.ubuntu.com/ubuntu/ hoary-security main restricted universe multiverse
#
deb-src http://archive.ubuntu.com/ubuntu/ hoary-updates main restricted universe multiverse
#
deb-src http://archive.ubuntu.com/ubuntu/ hoary main restricted universe multiverse
#
 
#
#deb ftp://ftp.nerim.net/debian-marillat testing main