Problém s aktualizáciou repozitárov 12.04

[inskeu]

Ahojte,

nainštaloval som si Ubuntu 12.04 LTS, konkrétne Linux Mint 13 (maya). Pri aktualizácii mi stále vypisuje nasledovnú hlášku:

The repository may no longer be available or could not be contacted because of network problems. If available an older version of the failed index will be used. Otherwise the repository will be ignored. Check your network connection and ensure the repository address in the preferences is correct.

Failed to fetch http://packages.medibuntu.org/dists/precise/Release.gpg  Something wicked happened resolving 'packages.medibuntu.org:http' (-5 - No address associated with hostname)
Failed to fetch http://packages.medibuntu.org/dists/precise/free/binary-amd64/Packages  Something wicked happened resolving 'packages.medibuntu.org:http' (-5 - No address associated with hostname)
Failed to fetch http://packages.medibuntu.org/dists/precise/non-free/binary-amd64/Packages  Something wicked happened resolving 'packages.medibuntu.org:http' (-5 - No address associated with hostname)
Failed to fetch http://packages.medibuntu.org/dists/precise/free/binary-i386/Packages  Something wicked happened resolving 'packages.medibuntu.org:http' (-5 - No address associated with hostname)
Failed to fetch http://packages.medibuntu.org/dists/precise/non-free/binary-i386/Packages  Something wicked happened resolving 'packages.medibuntu.org:http' (-5 - No address associated with hostname)
Failed to fetch http://packages.medibuntu.org/dists/precise/free/i18n/Translation-en_US  Something wicked happened resolving 'packages.medibuntu.org:http' (-5 - No address associated with hostname)
Failed to fetch http://packages.medibuntu.org/dists/precise/free/i18n/Translation-en  Something wicked happened resolving 'packages.medibuntu.org:http' (-5 - No address associated with hostname)
Failed to fetch http://packages.medibuntu.org/dists/precise/non-free/i18n/Translation-en_US  Something wicked happened resolving 'packages.medibuntu.org:http' (-5 - No address associated with hostname)
Failed to fetch http://packages.medibuntu.org/dists/precise/non-free/i18n/Translation-en  Something wicked happened resolving 'packages.medibuntu.org:http' (-5 - No address associated with hostname)
Some index files failed to download. They have been ignored, or old ones used instead.

V Linuxe nie som až tak veľmi zbehlý, čo treba nastaviť aby to fungovalo?

Vďaka za rady

[inskeu]

Ďakujem, pomohlo