Менеджер обновлений не работает на Efika MX (Ubuntu Maverick)

Когда я пытаюсь выполнить обновление с помощью диспетчера обновлений, я получаю следующее сообщение об ошибке:

Failed to download repository information: Check your Internet connection. W:Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/maverick/main/source/Sources.gz 404 Not Found, W:Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/maverick/restricted/source/Sources.gz 404 Not Found, W:Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/maverick/universe/source/Sources.gz 404 Not Found, W:Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/maverick/multiverse/source/Sources.gz 404 Not Found, W:Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/maverick/main/binary-armel/Packages.gz 404 Not Found, W:Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/maverick/restricted/binary-armel/Packages.gz 404 Not Found, W:Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/maverick/universe/binary-armel/Packages.gz 404 Not Found, W:Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/maverick/multiverse/binary-armel/Packages.gz 404 Not Found, W:Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/maverick-updates/main/source/Sources.gz 404 Not Found, W:Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/maverick-updates/restricted/source/Sources.gz 404 Not Found, W:Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/maverick-updates/universe/source/Sources.gz 404 Not Found, W:Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/maverick-updates/multiverse/source/Sources.gz 404 Not Found, W:Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/maverick-updates/main/binary-armel/Packages.gz 404 Not Found, W:Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/maverick-updates/restricted/binary-armel/Packages.gz 404 Not Found, W:Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/maverick-updates/universe/binary-armel/Packages.gz 404 Not Found, W:Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/maverick-updates/multiverse/binary-armel/Packages.gz 404 Not Found, W:Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/maverick-security/main/source/Sources.gz 404 Not Found, W:Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/maverick-security/restricted/source/Sources.gz 404 Not Found, W:Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/maverick-security/universe/source/Sources.gz 404 Not Found, W:Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/maverick-security/multiverse/source/Sources.gz 404 Not Found, W:Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/maverick-security/main/binary-armel/Packages.gz 404 Not Found, W:Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/maverick-security/restricted/binary-armel/Packages.gz 404 Not Found, W:Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/maverick-security/universe/binary-armel/Packages.gz 404 Not Found, W:Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/maverick-security/multiverse/binary-armel/Packages.gz 404 Not Found, E:Some index files failed to download, they have been ignored, or old ones used instead. 

Я знаю, что Maverick - это старая и неподдерживаемая версия, но я не могу перейти на новую версию, потому что Efika MX не поддерживает их. Я попытался заменить "port.ubuntu.com" на "old-releases.ubuntu.com" (как рекомендовали некоторые сайты), но он тоже не работает.

Какую конфигурацию я должен изменить, чтобы обновления работали правильно?