Buongiorno a tutti ho un problema nel gestore aggiornamenti quando clicco su verifica mi esce questo messaggio : W:GPG error: http://packages.medibuntu.org maverick Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 2EBC26B60C5A2783, W:Failed to fetch http://ppa.launchpad.net/stiff.ru/qmmp-release/ubuntu/dists/maverick/main/source/Sources.gz 404 Not Found
, W:Failed to fetch http://ppa.launchpad.net/stiff.ru/qmmp-release/ubuntu/dists/maverick/main/binary-i386/Packages.gz 404 Not Found
, E:Some index files failed to download, they have been ignored, or old ones used instead. Qualcuno può aiutarmi ?