sudo gedit /etc/apt/sources.listو کل محتویاتش رو پاک کنید و با این محتویات جایگزین کنید:############################################
#### Ubuntu Official Supported Packages ####
############################################
#### Main ####
#### Updates ####
deb http://archive.ubuntu.com/ubuntu/ gutsy-updates main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ gutsy-updates main restricted universe multiverse #Added by software-properties
#### Security Updates ####
deb http://security.ubuntu.com/ubuntu gutsy-security main restricted universe multiverse
deb-src http://security.ubuntu.com/ubuntu gutsy-security main restricted universe multiverse #Added by software-properties
#### Sources ####
#######################################################
##### Ubuntu Official Community Supported Packages ####
#######################################################
#### Universe/Multiverse - Main ####
##### Universe/Multiverse - Updates #####
##### Backports Project ####
deb http://archive.ubuntu.com/ubuntu/ gutsy-backports main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ gutsy-backports main restricted universe multiverse #Added by software-properties
##### Universe/Multiverse - Security Updates ####
#### Ubuntu Proposed packages ####
deb http://archive.ubuntu.com/ubuntu gutsy-proposed main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu gutsy-proposed main restricted universe multiverse #Added by software-properties
#### Canonical Commercial ####
##(Hosted on Canonical servers, not Ubuntu servers. RealPlayer10, Opera and more to come.)
deb http://archive.canonical.com/ubuntu gutsy partner
#### Sources ####
deb-src http://archive.canonical.com/ubuntu gutsy partner
######################################
#### Unofficial/Unsupported Repos ####
######################################
#### The Repository of Ubuntu Iran
## GPG key-file: wget -q http://archive.ubuntu.ir/ubuntu/ubuntu-ir-archive-key.gpg -O- | sudo apt-key add -
deb http://archive.ubuntu.ir/ubuntu/ gutsy main non-free
deb-src http://archive.ubuntu.ir/ubuntu/ gutsy main non-free
#### Medibuntu - Ubuntu 7.10 "gutsy gibbon"
## GPG key-file: wget -q http://packages.medibuntu.org/medibuntu-key.gpg -O- | sudo apt-key add -
## Please report any bug on https://bugs.launchpad.net/medibuntu/
deb http://packages.medibuntu.org/ gutsy free non-free
deb-src http://packages.medibuntu.org/ gutsy free non-free
#### Bleeding edge "wine" packages
## GPG key-file: wget -q http://wine.budgetdedicated.com/apt/387EE263.gpg -O- | sudo apt-key add -
deb http://wine.budgetdedicated.com/apt gutsy main
deb-src http://wine.budgetdedicated.com/apt gutsy main
#### Seveas’ packages (GPG key: 1135D466)
## GPG key-file: wget -q http://mirror.ubuntulinux.nl/1135D466.gpg -O- | sudo apt-key add -
deb http://mirror.ubuntulinux.nl gutsy-seveas all
deb-src http://mirror.ubuntulinux.nl gutsy-seveas all
#### UbuntuStudio Repository (GPG key: B6A4EB33)
# GPG key-file: gpg --keyserver subkeys.pgp.net --recv B6A4EB33 && gpg --export --armor B6A4EB33 | sudo apt-key add -
deb http://archive.ubuntustudio.org/ubuntustudio gutsy main
deb-src http://archive.ubuntustudio.org/ubuntustudio gutsy main
#### Upstream Opera (GPG key: 6A423791)
# GPG key-file: gpg --keyserver subkeys.pgp.net --recv 6A423791 && gpg --export --armor 6A423791 | sudo apt-key add -
deb http://deb.opera.com/opera etch non-free
#### Upstream Beryl (GPG key: 6A7476EA)
# GPG key-file: gpg --keyserver subkeys.pgp.net --recv 3FF0DB166A7476EA && gpg --export --armor 3FF0DB166A7476EA | sudo apt-key add -
deb http://ubuntu.beryl-project.org/ edgy main
deb-src http://ubuntu.beryl-project.org/ edgy main
#### Elbuntu - e17 desktop for ubuntu
## GPG key-file: gpg --keyserver subkeys.pgp.net --recv A7C6F0DF && gpg --export --armor A7C6F0DF | sudo apt-key add -
deb http://e17.dunnewind.net/ubuntu gutsy e17
#### Exaile - flexible audio player, similar to Amarok, but written in GTK+
## GPG Key: wget -q http://download.tuxfamily.org/syzygy42/reacocard.asc -O- | sudo apt-key add -
deb http://download.tuxfamily.org/syzygy42 gutsy exaile
deb http://download.tuxfamily.org/3v1deb gutsy eyecandy
deb-src http://download.tuxfamily.org/3v1deb gutsy eyecandy
deb http://archive.ubuntu.com/ubuntu/ gutsy main universe restricted multiverse
deb-src http://archive.ubuntu.com/ubuntu/ gutsy universe main multiverse restricted
deb http://download.tuxfamily.org/syzygy42 gutsy avant-window-navigator
deb-src http://download.tuxfamily.org/syzygy42 gutsy avant-window-navigator
# GPG key-file: gpg --keyserver subkeys.pgp.net --recv F854AFD7 && gpg --export --armor F854AFD7 | sudo apt-key add -
deb http://hendrik.kaju.pri.ee/ubuntu gutsy screenlets
deb http://getswiftfox.com/builds/debian unstable non-free
# GPG key-file: wget http://www.telemail.fi/mlind/ubuntu/937215FF.gpg -O- | sudo apt-key add -
deb http://www.telemail.fi/mlind/ubuntu gutsy fonts
deb-src http://www.telemail.fi/mlind/ubuntu gutsy fonts
deb http://www.telemail.fi/mlind/ubuntu gutsy experimental
deb-src http://www.telemail.fi/mlind/ubuntu gutsy experimental
deb http://backports.dereferenced.org/ gutsy universe
sudo apt-get updateالبته این دستورالعمل برای توزیع 7.10 که Gutsy نام داره هست. اگر از توزیع دیگهای استفاده می کنید، لازم هست که در متن بالا، تمام کلمه های gutsy رو با اسم توزیعتون عوض کنید.wget -q http://mirror.ubuntulinux.nl/1135D466.gpg -O- | sudo apt-key add -