Thread: GPG errors

trying
add
deb http://ppa.launchpad.net/pmcenery/ppa/ubuntu karmic main
sources list
in order (attempt to) connect ipod touch, after a

sudo apt-get update

have following errors don't understand - can please advise ?

errors
w: gpg error: http://dl.google.com testing release: following signatures couldn't verified because public key not available: no_pubkey a040830f7fac5991
w: gpg error: http://ppa.launchpad.net karmic release: following signatures couldn't verified because public key not available: no_pubkey 4ea3a911d48b8e25
w: duplicate sources.list entry http://ppa.launchpad.net karmic/main packages (/var/lib/apt/lists/ppa.launchpad.net_chromium-daily_ppa_ubuntu_dists_karmic_main_binary-i386_packages

sources list
# deb cdrom:[ubuntu 9.10 _karmic koala_ - release i386 (20091028.5)]/ karmic main restricted
# see http://help.ubuntu.com/community/upgradenotes how upgrade to
# newer versions of distribution.

deb http://gb.archive.ubuntu.com/ubuntu/ karmic main restricted
deb-src http://gb.archive.ubuntu.com/ubuntu/ karmic main restricted

## major bug fix updates produced after final release of the
## distribution.
deb http://gb.archive.ubuntu.com/ubuntu/ karmic-updates main restricted
deb-src http://gb.archive.ubuntu.com/ubuntu/ karmic-updates main restricted

## n.b. software repository entirely unsupported ubuntu
## team. also, please note software in universe not receive any
## review or updates ubuntu security team.
deb http://gb.archive.ubuntu.com/ubuntu/ karmic universe
deb-src http://gb.archive.ubuntu.com/ubuntu/ karmic universe
deb http://gb.archive.ubuntu.com/ubuntu/ karmic-updates universe
deb-src http://gb.archive.ubuntu.com/ubuntu/ karmic-updates universe

## n.b. software repository entirely unsupported ubuntu
## team, , may not under free licence. please satisfy
## rights use software. also, please note software in
## multiverse not receive review or updates ubuntu
## security team.
deb http://gb.archive.ubuntu.com/ubuntu/ karmic multiverse
deb-src http://gb.archive.ubuntu.com/ubuntu/ karmic multiverse
deb http://gb.archive.ubuntu.com/ubuntu/ karmic-updates multiverse
deb-src http://gb.archive.ubuntu.com/ubuntu/ karmic-updates multiverse

## uncomment following 2 lines add software 'backports'
## repository.
## n.b. software repository may not have been tested as
## extensively contained in main release, although includes
## newer versions of applications may provide useful features.
## also, please note software in backports not receive review
## or updates ubuntu security team.
# deb http://gb.archive.ubuntu.com/ubuntu/ karmic-backports main restricted universe multiverse
# deb-src http://gb.archive.ubuntu.com/ubuntu/ karmic-backports main restricted universe multiverse

## uncomment following 2 lines add software canonical's
## 'partner' repository.
## software not part of ubuntu, offered canonical , the
## respective vendors service ubuntu users.
deb http://archive.canonical.com/ubuntu karmic partner
# deb-src http://archive.canonical.com/ubuntu karmic partner

deb http://security.ubuntu.com/ubuntu karmic-security main restricted
deb-src http://security.ubuntu.com/ubuntu karmic-security main restricted
deb http://security.ubuntu.com/ubuntu karmic-security universe
deb-src http://security.ubuntu.com/ubuntu karmic-security universe
deb http://security.ubuntu.com/ubuntu karmic-security multiverse
deb-src http://security.ubuntu.com/ubuntu karmic-security multiverse
deb http://packages.medibuntu.org/ karmic free non-free
deb http://ppa.launchpad.net/chromium-daily/ppa/ubuntu karmic main
deb http://linux.dropbox.com/ubuntu karmic main
deb-src http://linux.dropbox.com/ubuntu karmic main
deb http://dl.google.com/linux/deb/ testing non-free
deb http://ppa.launchpad.net/pmcenery/ppa/ubuntu karmic main

try link in sig

Forum The Ubuntu Forum Community Ubuntu Official Flavours Support Installation & Upgrades [ubuntu] GPG errors

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