Abra /etc/apt/sources.list
em um editor como raiz (por exemplo, digite no terminal gksudo gedit /etc/apt/sources.list
) e substitua todo o seu conteúdo pelo seguinte
#############################################################
################### OFFICIAL UBUNTU REPOS ###################
#############################################################
###### Ubuntu Main Repos
deb http://us.archive.ubuntu.com/ubuntu/ trusty main restricted universe multiverse
deb-src http://us.archive.ubuntu.com/ubuntu/ trusty main restricted universe multiverse
###### Ubuntu Update Repos
deb http://us.archive.ubuntu.com/ubuntu/ trusty-security main restricted universe multiverse
deb http://us.archive.ubuntu.com/ubuntu/ trusty-updates main restricted universe multiverse
deb http://us.archive.ubuntu.com/ubuntu/ trusty-backports main restricted universe multiverse
deb-src http://us.archive.ubuntu.com/ubuntu/ trusty-security main restricted universe multiverse
deb-src http://us.archive.ubuntu.com/ubuntu/ trusty-updates main restricted universe multiverse
deb-src http://us.archive.ubuntu.com/ubuntu/ trusty-backports main restricted universe multiverse
###### Ubuntu Partner Repo
deb http://archive.canonical.com/ubuntu trusty partner
deb-src http://archive.canonical.com/ubuntu trusty partner
###### Ubuntu Extras Repo
deb http://extras.ubuntu.com/ubuntu trusty main
deb-src http://extras.ubuntu.com/ubuntu trusty main
Seu problema é que neste arquivo, em vez de repositorires, algum tipo de saída de um comando. Eu não tenho ideia de como chegou lá, você provavelmente sabe disso.