Não consigo atualizar. Eu também tentei update-manager . Dá a mensagem de erro: Falha ao baixar informações do repositório, verifique sua conexão com a Internet .
praveen@praveen-desktop:~$ sudo apt-get update
Hit http://archive.ubuntu.com raring Release.gpg
Hit http://archive.ubuntu.com raring-updates Release.gpg
Get:1 http://archive.canonical.com raring Release.gpg [933 B]
Hit http://archive.ubuntu.com raring-backports Release.gpg
Hit http://archive.canonical.com precise Release.gpg
Hit http://archive.ubuntu.com raring-security Release.gpg
Hit http://archive.canonical.com raring Release.gpg
Hit http://archive.ubuntu.com raring Release
Get:2 http://archive.canonical.com raring Release [5,919 B]
Hit http://archive.ubuntu.com raring-updates Release
Hit http://archive.ubuntu.com raring-backports Release
Hit http://archive.canonical.com precise Release
Hit http://archive.ubuntu.com raring-security Release
Hit http://archive.canonical.com raring Release
Hit http://archive.ubuntu.com raring/main Sources
Get:3 http://archive.canonical.com raring/partner Sources [2,693 B]
Hit http://archive.ubuntu.com raring/restricted Sources
Get:4 http://archive.canonical.com raring/partner amd64 Packages [3,641 B]
Hit http://archive.ubuntu.com raring/universe Sources
Get:5 http://archive.canonical.com raring/partner i386 Packages [4,792 B]
Hit http://archive.ubuntu.com raring/multiverse Sources
Get:6 http://ppa.launchpad.net raring Release.gpg [316 B]
Hit http://archive.ubuntu.com raring/main amd64 Packages
Ign http://ppa.launchpad.net raring Release.gpg
Hit http://archive.ubuntu.com raring/restricted amd64 Packages
Get:7 http://ppa.launchpad.net raring Release.gpg [316 B]
Get:8 http://archive.canonical.com precise/partner Sources [5,215 B]
Hit http://ppa.launchpad.net raring Release.gpg
Hit http://archive.ubuntu.com raring/universe amd64 Packages
Hit http://ppa.launchpad.net raring Release.gpg
Hit http://archive.ubuntu.com raring/multiverse amd64 Packages
Hit http://ppa.launchpad.net raring Release.gpg
Hit http://archive.canonical.com precise/partner amd64 Packages
Hit http://ppa.launchpad.net raring Release.gpg
Hit http://archive.ubuntu.com raring/main i386 Packages
Hit http://archive.canonical.com precise/partner i386 Packages
Hit http://ppa.launchpad.net raring Release
Hit http://archive.ubuntu.com raring/restricted i386 Packages
Ign http://ppa.launchpad.net raring Release
Hit http://archive.ubuntu.com raring/universe i386 Packages
Hit http://ppa.launchpad.net raring Release
Ign http://ppa.launchpad.net raring Release
Get:9 http://archive.canonical.com raring/partner Sources [2,693 B]
Hit http://archive.ubuntu.com raring/multiverse i386 Packages
Hit http://ppa.launchpad.net raring Release
Hit http://archive.canonical.com raring/partner amd64 Packages
Hit http://ppa.launchpad.net raring Release
Hit http://archive.canonical.com raring/partner i386 Packages
Hit http://archive.ubuntu.com raring/main Translation-en
Hit http://ppa.launchpad.net raring Release
Hit http://ppa.launchpad.net raring Release
Hit http://archive.ubuntu.com raring/multiverse Translation-en
Get:10 http://ppa.launchpad.net raring/main Sources [1,659 B]
Hit http://ppa.launchpad.net raring/main amd64 Packages
Hit http://ppa.launchpad.net raring/main i386 Packages
Hit http://archive.ubuntu.com raring/restricted Translation-en
Hit http://archive.ubuntu.com raring/universe Translation-en
Hit http://archive.ubuntu.com raring-updates/main Sources
Hit http://archive.ubuntu.com raring-updates/restricted Sources
Hit http://archive.ubuntu.com raring-updates/universe Sources
Hit http://archive.ubuntu.com raring-updates/multiverse Sources
Hit http://archive.ubuntu.com raring-updates/main amd64 Packages
Hit http://archive.ubuntu.com raring-updates/restricted amd64 Packages
Get:11 http://ppa.launchpad.net raring/main Sources [743 B]
Ign http://ppa.launchpad.net raring/main amd64 Packages/DiffIndex
Ign http://ppa.launchpad.net raring/main i386 Packages/DiffIndex
Hit http://archive.ubuntu.com raring-updates/universe amd64 Packages
Hit http://archive.ubuntu.com raring-updates/multiverse amd64 Packages
Hit http://archive.ubuntu.com raring-updates/main i386 Packages
Get:12 http://ppa.launchpad.net raring/main Sources [9,222 B]
Hit http://archive.ubuntu.com raring-updates/restricted i386 Packages
Hit http://archive.ubuntu.com raring-updates/universe i386 Packages
Hit http://ppa.launchpad.net raring/main amd64 Packages
Hit http://archive.ubuntu.com raring-updates/multiverse i386 Packages
Hit http://ppa.launchpad.net raring/main i386 Packages
Ign http://archive.canonical.com raring/partner Translation-en_IN
Hit http://archive.ubuntu.com raring-updates/main Translation-en
Ign http://archive.canonical.com raring/partner Translation-en
Get:13 http://ppa.launchpad.net raring/main Sources [11.5 kB]
Ign http://archive.canonical.com precise/partner Translation-en_IN
Hit http://archive.ubuntu.com raring-updates/multiverse Translation-en
Ign http://archive.canonical.com precise/partner Translation-en
Ign http://archive.canonical.com raring/partner Translation-en_IN
Hit http://ppa.launchpad.net raring/main amd64 Packages
Hit http://archive.ubuntu.com raring-updates/restricted Translation-en
Ign http://archive.canonical.com raring/partner Translation-en
Hit http://ppa.launchpad.net raring/main i386 Packages
Hit http://archive.ubuntu.com raring-updates/universe Translation-en
Hit http://archive.ubuntu.com raring-backports/main Sources
Get:14 http://ppa.launchpad.net raring/main Sources [657 B]
Hit http://archive.ubuntu.com raring-backports/restricted Sources
Hit http://ppa.launchpad.net raring/main amd64 Packages
Hit http://archive.ubuntu.com raring-backports/universe Sources
Hit http://ppa.launchpad.net raring/main i386 Packages
Hit http://archive.ubuntu.com raring-backports/multiverse Sources
Hit http://archive.ubuntu.com raring-backports/main amd64 Packages
Get:15 http://ppa.launchpad.net raring/main Sources [603 B]
Ign https://private-ppa.launchpad.net raring Release.gpg
Hit http://ppa.launchpad.net raring/main amd64 Packages
Hit http://archive.ubuntu.com raring-backports/restricted amd64 Packages
Hit http://ppa.launchpad.net raring/main i386 Packages
Hit http://archive.ubuntu.com raring-backports/universe amd64 Packages
Hit http://archive.ubuntu.com raring-backports/multiverse amd64 Packages
Hit http://archive.ubuntu.com raring-backports/main i386 Packages
Hit http://archive.ubuntu.com raring-backports/restricted i386 Packages
Hit http://archive.ubuntu.com raring-backports/universe i386 Packages
Hit http://archive.ubuntu.com raring-backports/multiverse i386 Packages
Hit http://archive.ubuntu.com raring-backports/main Translation-en
Hit http://archive.ubuntu.com raring-backports/multiverse Translation-en
Hit http://ppa.launchpad.net raring/main amd64 Packages
Err http://extras.ubuntu.com raring Release.gpg
Something wicked happened resolving 'extras.ubuntu.com:http' (-11 - System error)
Hit http://ppa.launchpad.net raring/main i386 Packages
Hit http://archive.ubuntu.com raring-backports/restricted Translation-en
Hit http://archive.ubuntu.com raring-backports/universe Translation-en
Hit http://archive.ubuntu.com raring-security/main Sources
Hit http://archive.ubuntu.com raring-security/restricted Sources
Hit http://archive.ubuntu.com raring-security/universe Sources
Hit http://archive.ubuntu.com raring-security/multiverse Sources
Hit http://archive.ubuntu.com raring-security/main amd64 Packages
Hit http://archive.ubuntu.com raring-security/restricted amd64 Packages
Hit http://archive.ubuntu.com raring-security/universe amd64 Packages
Hit http://archive.ubuntu.com raring-security/multiverse amd64 Packages
Hit http://archive.ubuntu.com raring-security/main i386 Packages
Hit http://archive.ubuntu.com raring-security/restricted i386 Packages
Hit http://archive.ubuntu.com raring-security/universe i386 Packages
Hit http://archive.ubuntu.com raring-security/multiverse i386 Packages
Hit http://archive.ubuntu.com raring-security/main Translation-en
Hit https://private-ppa.launchpad.net raring Release
Ign https://private-ppa.launchpad.net raring/main amd64 Packages/DiffIndex
Hit http://archive.ubuntu.com raring-security/multiverse Translation-en
Hit http://archive.ubuntu.com raring-security/restricted Translation-en
Ign https://private-ppa.launchpad.net raring/main i386 Packages/DiffIndex
Hit http://archive.ubuntu.com raring-security/universe Translation-en
Hit https://private-ppa.launchpad.net raring/main amd64 Packages
Hit https://private-ppa.launchpad.net raring/main i386 Packages
Ign http://ppa.launchpad.net raring/main Translation-en_IN
Ign http://ppa.launchpad.net raring/main Translation-en
Err http://ppa.launchpad.net raring/main Sources
404 Not Found
Err http://ppa.launchpad.net raring/main amd64 Packages
404 Not Found
Err http://ppa.launchpad.net raring/main i386 Packages
404 Not Found
Hit http://extras.ubuntu.com raring Release
Ign http://ppa.launchpad.net raring/main Translation-en_IN
Ign http://extras.ubuntu.com raring/main Sources/DiffIndex
Ign http://ppa.launchpad.net raring/main Translation-en
Ign http://extras.ubuntu.com raring/main amd64 Packages/DiffIndex
Ign http://extras.ubuntu.com raring/main i386 Packages/DiffIndex
Ign http://ppa.launchpad.net raring/main Translation-en_IN
Hit http://extras.ubuntu.com raring/main Sources
Ign http://ppa.launchpad.net raring/main Translation-en
Hit http://extras.ubuntu.com raring/main amd64 Packages
Ign http://ppa.launchpad.net raring/main Translation-en_IN
Hit http://extras.ubuntu.com raring/main i386 Packages
Ign http://ppa.launchpad.net raring/main Translation-en
Ign http://ppa.launchpad.net raring/main Translation-en_IN
Ign http://ppa.launchpad.net raring/main Translation-en
Ign http://ppa.launchpad.net raring/main Translation-en_IN
Ign http://ppa.launchpad.net raring/main Translation-en
Ign http://ppa.launchpad.net raring/main Translation-en_IN
Ign http://ppa.launchpad.net raring/main Translation-en
Ign http://extras.ubuntu.com raring/main Translation-en_IN
Ign http://extras.ubuntu.com raring/main Translation-en
Ign https://private-ppa.launchpad.net raring/main Translation-en_IN
Ign https://private-ppa.launchpad.net raring/main Translation-en
Ign http://archive.ubuntu.com raring/main Translation-en_IN
Ign http://archive.ubuntu.com raring/multiverse Translation-en_IN
Ign http://archive.ubuntu.com raring/restricted Translation-en_IN
Ign http://archive.ubuntu.com raring/universe Translation-en_IN
Ign http://archive.ubuntu.com raring-updates/main Translation-en_IN
Ign http://archive.ubuntu.com raring-updates/multiverse Translation-en_IN
Ign http://archive.ubuntu.com raring-updates/restricted Translation-en_IN
Ign http://archive.ubuntu.com raring-updates/universe Translation-en_IN
Ign http://archive.ubuntu.com raring-backports/main Translation-en_IN
Ign http://archive.ubuntu.com raring-backports/multiverse Translation-en_IN
Ign http://archive.ubuntu.com raring-backports/restricted Translation-en_IN
Ign http://archive.ubuntu.com raring-backports/universe Translation-en_IN
Ign http://archive.ubuntu.com raring-security/main Translation-en_IN
Ign http://archive.ubuntu.com raring-security/multiverse Translation-en_IN
Ign http://archive.ubuntu.com raring-security/restricted Translation-en_IN
Ign http://archive.ubuntu.com raring-security/universe Translation-en_IN
Fetched 50.9 kB in 1min 10s (722 B/s)
W: GPG error: http://ppa.launchpad.net raring Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 7B1AB59047B4D1C4
W: Failed to fetch http://extras.ubuntu.com/ubuntu/dists/raring/Release.gpg Something wicked happened resolving 'extras.ubuntu.com:http' (-11 - System error)
W: Failed to fetch http://ppa.launchpad.net/guadalinex-members/ppa/ubuntu/dists/raring/main/source/Sources 404 Not Found
W: Failed to fetch http://ppa.launchpad.net/guadalinex-members/ppa/ubuntu/dists/raring/main/binary-amd64/Packages 404 Not Found
W: Failed to fetch http://ppa.launchpad.net/guadalinex-members/ppa/ubuntu/dists/raring/main/binary-i386/Packages 404 Not Found
E: Some index files failed to download. They have been ignored, or old ones used instead.
W: Failed to fetch http://ppa.launchpad.net/guadalinex-members/ppa/ubuntu/dists/raring/main/source/Sources 404 Not Found
Esse erro significa que você está usando um PPA que não oferece pacotes Raring.
O PPA é " PPA para os membros da Guadalinex ". Para removê-lo, use ppa-purge :
ppa-purge ppa:guadalinex-members/ppa