mensagem de erro ao sudo apt-get update

xiloba
(usa Slackware)

Enviado em 16/05/2011 - 21:11h

Estou tendo a mensagem de erro ao atualizar o sistema:
W: Erro GPG: http://ppa.launchpad.net lucid Release: As assinaturas a seguir não puderam ser verificadas devido à chave pública não estar disponível: NO_PUBKEY 7D2C7A23BF810CD5
Já fui em "gerenciador de atualizações>configurações> outro software e não consigo identificar pois tenho 8 começando com http://ppa.launchpad.net . Qual deles usa a chave 7D2C7A23BF810CD5 ?
Existe como eu direcionar a saída do comando para listar a relação destes outros sftwares?
algo tipo gedit lugar onde fica relação de outros softwares >txt ?

xiloba
(usa Slackware)

Enviado em 17/05/2011 - 12:08h

Olha, abir a lista com meus repositórios eu aprendi:
gedit /etc/apt/sources.list
ou cat -b /etc/apt/sources.list >txt (cria um arquivo .txt com a lista de repositórios, numeradas as listas por conta do comando -b)

o
# deb cdrom:[Ubuntu 10.04.1 LTS _Lucid Lynx_ - Release amd64 (20100816.1)]/ lucid 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/ lucid main restricted
deb-src http://br.archive.ubuntu.com/ubuntu/ lucid main restricted

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

## Uncomment the following two lines to add software from the 'backports'
## repository.
## 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/ lucid-backports main restricted universe multiverse
# deb-src http://br.archive.ubuntu.com/ubuntu/ lucid-backports main restricted universe 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">http://archive.canonical.com/ubuntu lucid partner
# deb-src http://archive.canonical.com/ubuntu">http://archive.canonical.com/ubuntu lucid partner

deb http://security.ubuntu.com/ubuntu lucid-security main restricted
deb-src http://security.ubuntu.com/ubuntu lucid-security main restricted
deb http://security.ubuntu.com/ubuntu lucid-security universe
deb-src http://security.ubuntu.com/ubuntu lucid-security universe
deb http://security.ubuntu.com/ubuntu lucid-security multiverse
deb-src http://security.ubuntu.com/ubuntu lucid-security multiverse
deb http://archive.canonical.com/ lucid partner
# deb http://www.remastersys.klikit-linux.com/repository remastersys/
# deb http://www.remastersys.klikit-linux.com/repository remastersys/
# deb http://www.geekconnection.org/remastersys/repository karmic/
deb http://ppa.launchpad.net/dockbar-main/ppa/ubuntu lucid main
deb http://ppa.launchpad.net/gnomenu-team/ppa/ubuntu lucid main
deb http://ppa.launchpad.net/elementaryart/elementarydesktop/ubuntu lucid main
deb http://www.geekconnection.org/remastersys/repository karmic/

mas continuo sem saber o que está gerando o erro nos repositórios