[eth0]

sudo cp /etc/apt/sources.list /etc/apt/sources.list_backup
sudo gedit /etc/apt/sources.list

Zastąp całą zawartość pliku następującym wpisem

## Add comments (##) in front of any line to remove it from being checked.
## Use the following sources.list at your own risk.
## You may replace "us" with your country code to get the closest mirror.

deb http://us.archive.ubuntu.com/ubuntu dapper main restricted
deb-src http://us.archive.ubuntu.com/ubuntu dapper main restricted

## MAJOR BUG FIX UPDATES produced after the final release
deb http://us.archive.ubuntu.com/ubuntu dapper-updates main restricted
deb-src http://us.archive.ubuntu.com/ubuntu dapper-updates main restricted

## UBUNTU SECURITY UPDATES
deb http://security.ubuntu.com/ubuntu dapper-security main restricted
deb-src http://security.ubuntu.com/ubuntu dapper-security main restricted

deb http://security.ubuntu.com/ubuntu dapper-security universe
deb-src http://security.ubuntu.com/ubuntu dapper-security universe

## UNIVERSE AND MULTIVERSE REPOSITORY (Unsupported by Ubuntu. Use at own risk.)
deb http://archive.ubuntu.com/ubuntu dapper universe multiverse
deb-src http://archive.ubuntu.com/ubuntu dapper universe multiverse

## BACKPORTS REPOSITORY (Unsupported. May contain illegal packages. Use at own risk.)
deb http://archive.ubuntu.com/ubuntu dapper-backports main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu dapper-backports main restricted universe multiverse

## PLF REPOSITORY (Unsupported. May contain illegal packages. Use at own risk.)
deb http://packages.freecontrib.org/ubuntu/plf dapper free non-free
deb-src http://packages.freecontrib.org/ubuntu/plf dapper free non-free

Zapisz tak przygotowany plik

sudo apt-get update