Removendo um PPA [RESOLVIDO]

Como faço para remover um repositorio PPA que adicionei via comando? Quando dou um apt-get update e após atualizar me aparece seguintes erros:

W: Falhou ao buscar http://ppa.launchpad.net/mozillateam/firefox-stable/ubuntu/dists/oneiric/main/source/Sources 404 Not Found

W: Falhou ao buscar http://ppa.launchpad.net/mozillateam/firefox-stable/ubuntu/dists/oneiric/main/binary-amd64/Packages 404 Not Found

W: Falhou ao buscar http://ppa.launchpad.net/mozillateam/firefox-stable/ubuntu/dists/oneiric/main/binary-i386/Packages 404 Not Found

E: Alguns arquivos index falharam ao ser baixados. Eles foram ignorados, ou cópias antigas são usadas ao invés.

E não sei como remover esses repositorio que adicionei para poder instalar o Firefox 8.

Todos os repositórios adicionados via ppa ficam no arquivo /etc/apt/sources.list


Abra o arquivo com o gedit (ou nano) como root:

gksu gedit /etc/apt/sources.list

Remova as linhas referentes ao ppa do Firefox e atualize os repositórios:

apt-get update

Se tiver alguma dificuldade, poste o conteúdo do arquivo /etc/apt/sources.list com o comando:

cat /etc/apt/sources.list

[]'s

Não conseguir identificar o Repositorio aí, e olha que procurei... segue o source.list


# deb cdrom:[Ubuntu 11.10 _Oneiric Ocelot_ - Release amd64 (20111012)]/ dists/oneiric/main/binary-i386/

# deb cdrom:[Ubuntu 11.10 _Oneiric Ocelot_ - Release amd64 (20111012)]/ oneiric main restricted

# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
# newer versions of the distribution.
deb http://br.archive.ubuntu.com/ubuntu/ oneiric main restricted
deb-src http://br.archive.ubuntu.com/ubuntu/ oneiric main restricted

## Major bug fix updates produced after the final release of the
## distribution.
deb http://br.archive.ubuntu.com/ubuntu/ oneiric-updates main restricted
deb-src http://br.archive.ubuntu.com/ubuntu/ oneiric-updates main restricted

## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team. Also, please note that software in universe WILL NOT receive any
## review or updates from the Ubuntu security team.
deb http://br.archive.ubuntu.com/ubuntu/ oneiric universe
deb-src http://br.archive.ubuntu.com/ubuntu/ oneiric universe
deb http://br.archive.ubuntu.com/ubuntu/ oneiric-updates universe
deb-src http://br.archive.ubuntu.com/ubuntu/ oneiric-updates universe

## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team, and may not be under a free licence. Please satisfy yourself as to
## your rights to use the software. Also, please note that software in
## multiverse WILL NOT receive any review or updates from the Ubuntu
## security team.
deb http://br.archive.ubuntu.com/ubuntu/ oneiric multiverse
deb-src http://br.archive.ubuntu.com/ubuntu/ oneiric multiverse
deb http://br.archive.ubuntu.com/ubuntu/ oneiric-updates multiverse
deb-src http://br.archive.ubuntu.com/ubuntu/ oneiric-updates multiverse

## N.B. software from this repository may not have been tested as
## extensively as that contained in the main release, although it includes
## newer versions of some applications which may provide useful features.
## Also, please note that software in backports WILL NOT receive any review
## or updates from the Ubuntu security team.
deb http://br.archive.ubuntu.com/ubuntu/ oneiric-backports main restricted universe multiverse
deb-src http://br.archive.ubuntu.com/ubuntu/ oneiric-backports main restricted universe multiverse

deb http://security.ubuntu.com/ubuntu oneiric-security main restricted
deb-src http://security.ubuntu.com/ubuntu oneiric-security main restricted
deb http://security.ubuntu.com/ubuntu oneiric-security universe
deb-src http://security.ubuntu.com/ubuntu oneiric-security universe
deb http://security.ubuntu.com/ubuntu oneiric-security multiverse
deb-src http://security.ubuntu.com/ubuntu oneiric-security multiverse

## Uncomment the following two lines to add software from Canonical's
## 'partner' repository.
## This software is not part of Ubuntu, but is offered by Canonical and the
## respective vendors as a service to Ubuntu users.
# deb http://archive.canonical.com/ubuntu oneiric partner
# deb-src http://archive.canonical.com/ubuntu oneiric partner

## This software is not part of Ubuntu, but is offered by third-party
## developers who want to ship their latest software.
deb http://extras.ubuntu.com/ubuntu oneiric main
deb-src http://extras.ubuntu.com/ubuntu oneiric main

Que estranho...

Qual o comando para adicionar o ppa do Firefox 8?

Vou fazer um teste aqui pra ver se dá erro também.

Apesar de não prestar atenção que era para versão 10.04 e 10.10 no console digitei:
sudo apt-add-repository ppa:mozillateam/firefox-stable

E no Update o erro.

Show de bola, resolveu minha vida. como sou novo no Ubuntu, não tenho costume ainda onde ficar algumas coisas. Vou testando ele para ver se da para adaptar. Obrigado!

Oláaa! Estou com o mesmo problema...

W: Falhou ao buscar http://ppa.launchpad.net/tualatrix/ppa/ubuntu/dists/vivid/main/binary-i386/Packages 404 Not Found

E: Falhou o download de alguns ficheiros de índice. Foram ignorados ou os antigos foram usados em seu lugar.

como resolvo isso?

Este tópico está resolvido. Crtie um com seu problema. Mas antes tente remover PPA problemáticos