The solution for apt-get update ERR 404

The following error occurred after the sudo apt-get Update command was recently executed on Ubuntu 12.10:

IGN http://extras.ubuntu.com natty/main TranslationindexERR http://extras.ubuntu.com natty/main Sources      404Not Found Err http://extras.ubuntu.com Natty/main i386 Packages      404Not Found Ign http://extras.ubuntu.com natty/main Translation-en_usERR http://security.ubuntu.com natty-security/universe Sources      404Not Found [IP:91.189.92.200  the] ERR http://security.ubuntu.com natty-security/multiverse Sources      404Not Found [IP:91.189.92.200  the] IGN http://extras.ubuntu.com natty/main Translation-enERR http://security.ubuntu.com natty-security/universe i386 Packages      404Not Found [IP:91.189.92.200  the] ERR http://security.ubuntu.com natty-security/multiverse i386 Packages      404Not Found [IP:91.189.92.200  the] ERR http://security.ubuntu.com natty-security/main Sources      404Not Found [IP:91.189.92.200  the] ERR http://security.ubuntu.com natty-security/restricted Sources      404Not Found [IP:91.189.92.200  the] ERR http://security.ubuntu.com Natty-security/main i386 Packages      404Not Found [IP:91.189.92.200  the] ERR http://security.ubuntu.com natty-security/restricted i386 Packages      404Not Found [IP:91.189.92.200  the] IGN http://security.ubuntu.com natty-security/main Translation-en_usIGN http://security.ubuntu.com natty-security/main Translation-enIGN http://security.ubuntu.com natty-security/multiverse Translation-en_usIGN http://security.ubuntu.com natty-security/multiverse Translation-enIGN http://security.ubuntu.com natty-security/restricted Translation-en_usIGN http://security.ubuntu.com natty-security/restricted Translation-enIGN http://security.ubuntu.com natty-security/universe Translation-en_usIGN http://security.ubuntu.com natty-security/universe Translation-enw:failed to fetch http://cn.archive.ubuntu.com/ubuntu/dists/natty/main/source/sources 404 Not Foundw:failed to fetch http://cn.archive.ubuntu.com/ubuntu/dists/natty/restricted/source/sources 404 Not Foundw:failed to fetch http://cn.archive.ubuntu.com/ubuntu/dists/natty/universe/source/sources 404 Not Foundw:failed to fetch http://cn.archive.ubuntu.com/ubuntu/dists/natty/multiverse/source/sources 404 Not Foundw:failed to fetch http://cn.archive.ubuntu.com/ubuntu/dists/natty/main/binary-i386/packages 404 Not Foundw:failed to fetch http://cn.archive.ubuntu.com/ubuntu/dists/natty/restricted/binary-i386/packages 404 Not Foundw:failed to fetch http://cn.archive.ubuntu.com/ubuntu/dists/natty/universe/binary-i386/packages 404 Not Foundw:failed to fetch http://cn.archive.ubuntu.com/ubuntu/dists/natty/multiverse/binary-i386/packages 404 Not Foundw:failed to fetch http://cn.archive.ubuntu.com/ubuntu/dists/natty-updates/main/source/sources 404 Not Foundw:failed to fetch http://cn.archive.ubuntu.com/ubuntu/dists/natty-updates/restricted/source/sources 404 Not Foundw:failed to fetch http://cn.archive.ubuntu.com/ubuntu/dists/natty-updates/universe/source/sources 404 Not Foundw:failed to fetch http://cn.archive.ubuntu.com/ubuntu/dists/natty-updates/multiverse/source/sources 404 Not Foundw:failed to fetch http://cn.archive.ubuntu.com/ubuntu/dists/natty-updates/main/binary-i386/packages 404 Not Foundw:failed to fetch http://cn.archive.ubuntu.com/ubuntu/dists/natty-updates/restricted/binary-i386/packages 404 Not Foundw:failed to fetch http://cn.archive.ubuntu.com/ubuntu/dists/natty-updates/universe/binary-i386/packages 404 Not Foundw:failed to fetch http://cn.archive.ubuntu.com/ubuntu/dists/natty-updates/multiverse/binary-i386/packages 404 Not Foundw:failed to fetch http://security.ubuntu.com/ubuntu/dists/natty-security/universe/source/sources 404 Not Found [ip:91.189.92.200 80] w:failed to fetch http://security.ubuntu.com/ubuntu/dists/natty-security/multiverse/source/sources 404 Not Found [ip:91.189.92.200 80] 
    w:failed to fetch http://security.ubuntu.com/ubuntu/dists/natty-security/universe/binary-i386/packages 404 Not Found [ip:91.189.92.200 []w:failed to fetch http://security.ubuntu.com/ubuntu/dists/natty-security/multiverse/binary-i386/packages 404 Not Found [IP: 91.189.92.200]w:failed to fetch http://security.ubuntu.com/ubuntu/dists/natty-security/main/source/sources 404 Not Found [ip:91.189.92.200]w:failed to fetch http://security.ubuntu.com/ubuntu/dists/natty-security/restricted/source/sources 404 Not Found [ip:91.189.92.200 80] 
    w:failed to fetch http://security.ubuntu.com/ubuntu/dists/natty-security/main/binary-i386/packages 404 Not Found [ip:91.189.92.200 80] 
    w:failed to fetch http://security.ubuntu.com/ubuntu/dists/natty-security/restricted/binary-i386/packages 404 Not Found [IP: 91.189.92.200]w:failed to fetch http://extras.ubuntu.com/ubuntu/dists/natty/main/source/sources 404 Not Foundw:failed to fetch http://extras.ubuntu.com/ubuntu/dists/natty/main/binary-i386/packages 404 Not FoundE:some index files failed to download.      They has been ignored, or old ones used instead. [Email protected]:~$sudoApt-getInstallgit Reading package lists ... Done Building Dependency Tree Reading state information ... Done E:unable toLocatePackage git

Found that many sources can not be found, need to re-find the update source, and finally replace the contents of the/etc/apt/sources.list file directly into:

Found this source super fast, is NetEase 163 update server, pro-Test available

Also attached
Sohu Update server:

This speed is also very fast, the domestic source is the Ox x ~ ~

The solution for apt-get update ERR 404