This is the output of the command # apt-get update. I cannot update any packages with update manager either. What is the problem?
Ign http://mirrors.dotsrc.org precise-getdeb InRelease
Ign http://ppa.launchpad.net precise InRelease
Ign http://ppa.launchpad.net precise InRelease
Ign http://ppa.launchpad.net precise InRelease
Ign http://ppa.launchpad.net precise InRelease
Get:1 http://www.remastersys.com precise InRelease [2,069 B]
Get:2 http://mirrors.dotsrc.org precise-getdeb Release.gpg [836 B]
Ign http://archive.ubuntu.com precise InRelease
Ign http://archive.ubuntu.com precise-updates InRelease
Ign http://archive.ubuntu.com precise-backports InRelease
Ign http://archive.ubuntu.com precise-security InRelease
Get:3 http://ppa.launchpad.net precise Release.gpg [316 B]
Hit http://ppa.launchpad.net precise Release.gpg
Hit http://mirrors.dotsrc.org precise-getdeb Release
Hit http://www.remastersys.com precise/main i386 Packages
Hit http://ppa.launchpad.net precise Release.gpg
Get:4 http://archive.ubuntu.com precise Release.gpg [198 B]
Hit http://mirrors.dotsrc.org precise-getdeb/apps i386 Packages
Get:5 http://archive.ubuntu.com precise-updates Release.gpg [198 B]
Get:6 http://archive.ubuntu.com precise-backports Release.gpg [198 B]
Hit http://ppa.launchpad.net precise Release.gpg
Ign http://www.remastersys.com precise/main TranslationIndex
Hit http://ppa.launchpad.net precise Release
Hit http://mirrors.dotsrc.org precise-getdeb/games i386 Packages
Get:7 http://archive.ubuntu.com precise-security Release.gpg [198 B]
Ign http://mirrors.dotsrc.org precise-getdeb/apps TranslationIndex
Ign http://mirrors.dotsrc.org precise-getdeb/games TranslationIndex
Hit http://ppa.launchpad.net precise Release
Get:8 http://archive.ubuntu.com precise Release [49.6 kB]
Hit http://ppa.launchpad.net precise Release
Hit http://ppa.launchpad.net precise Release
Hit http://ppa.launchpad.net precise/main i386 Packages
Ign http://ppa.launchpad.net precise/main TranslationIndex
Get:9 http://archive.ubuntu.com precise-updates Release [49.6 kB]
Hit http://ppa.launchpad.net precise/main i386 Packages
Get:10 http://archive.ubuntu.com precise-backports Release [49.6 kB]
Get:11 http://archive.ubuntu.com precise-security Release [49.6 kB]
Ign http://ppa.launchpad.net precise/main TranslationIndex
Hit http://ppa.launchpad.net precise/main i386 Packages
Ign http://ppa.launchpad.net precise/main TranslationIndex
Hit http://ppa.launchpad.net precise/main i386 Packages
Ign http://ppa.launchpad.net precise/main TranslationIndex
Get:12 http://archive.ubuntu.com precise/main Sources [934 kB]
Ign http://mirrors.dotsrc.org precise-getdeb/apps Translation-en_US
Get:13 http://archive.ubuntu.com precise/restricted Sources [5,470 B]
Get:14 http://archive.ubuntu.com precise/universe Sources [5,019 kB]
Ign http://www.remastersys.com precise/main Translation-en_US
Ign http://mirrors.dotsrc.org precise-getdeb/apps Translation-en
Ign http://mirrors.dotsrc.org precise-getdeb/apps Translation-bn
Ign http://mirrors.dotsrc.org precise-getdeb/games Translation-en_US
Ign http://mirrors.dotsrc.org precise-getdeb/games Translation-en
Ign http://www.remastersys.com precise/main Translation-en
Ign http://mirrors.dotsrc.org precise-getdeb/games Translation-bn
Ign http://www.remastersys.com precise/main Translation-bn
Ign http://ppa.launchpad.net precise/main Translation-en_US
Ign http://ppa.launchpad.net precise/main Translation-en
Ign http://ppa.launchpad.net precise/main Translation-bn
Ign http://ppa.launchpad.net precise/main Translation-en_US
Ign http://ppa.launchpad.net precise/main Translation-en
Ign http://ppa.launchpad.net precise/main Translation-bn
Ign http://ppa.launchpad.net precise/main Translation-en_US
Ign http://ppa.launchpad.net precise/main Translation-en
Ign http://ppa.launchpad.net precise/main Translation-bn
Ign http://ppa.launchpad.net precise/main Translation-en_US
Ign http://ppa.launchpad.net precise/main Translation-en
Ign http://ppa.launchpad.net precise/main Translation-bn
Get:15 http://archive.ubuntu.com precise/multiverse Sources [155 kB]
Get:16 http://archive.ubuntu.com precise/main i386 Packages [1,274 kB]
Get:17 http://archive.ubuntu.com precise/main i386 Packages [1,274 kB]
Get:18 http://archive.ubuntu.com precise/restricted i386 Packages [8,431 B]
Get:19 http://archive.ubuntu.com precise/universe i386 Packages [4,796 kB]
Get:20 http://archive.ubuntu.com precise/multiverse i386 Packages [121 kB]
Hit http://archive.ubuntu.com precise/main TranslationIndex
Hit http://archive.ubuntu.com precise/multiverse TranslationIndex
Hit http://archive.ubuntu.com precise/restricted TranslationIndex
Hit http://archive.ubuntu.com precise/universe TranslationIndex
Get:21 http://archive.ubuntu.com precise-updates/main Sources [46.9 kB]
Get:22 http://archive.ubuntu.com precise-updates/restricted Sources [1,379 B]
Get:23 http://archive.ubuntu.com precise-updates/universe Sources [14.4 kB]
Get:24 http://archive.ubuntu.com precise-updates/multiverse Sources [696 B]
Get:25 http://archive.ubuntu.com precise-updates/main i386 Packages [120 kB]
Get:26 http://archive.ubuntu.com precise-updates/restricted i386 Packages [2,439 B]
Get:27 http://archive.ubuntu.com precise-updates/universe i386 Packages [37.1 kB]
Get:28 http://archive.ubuntu.com precise-updates/multiverse i386 Packages [1,393 B]
Hit http://archive.ubuntu.com precise-updates/main TranslationIndex
Hit http://archive.ubuntu.com precise-updates/multiverse TranslationIndex
Hit http://archive.ubuntu.com precise-updates/restricted TranslationIndex
Hit http://archive.ubuntu.com precise-updates/universe TranslationIndex
Get:29 http://archive.ubuntu.com precise-backports/main Sources [700 B]
Get:30 http://archive.ubuntu.com precise-backports/restricted Sources [14 B]
Get:31 http://archive.ubuntu.com precise-backports/universe Sources [4,404 B]
Get:32 http://archive.ubuntu.com precise-backports/multiverse Sources [14 B]
Get:33 http://archive.ubuntu.com precise-backports/main i386 Packages [559 B]
Get:34 http://archive.ubuntu.com precise-backports/restricted i386 Packages [14 B]
Get:35 http://archive.ubuntu.com precise-backports/universe i386 Packages [3,167 B]
Get:36 http://archive.ubuntu.com precise-backports/multiverse i386 Packages [14 B]
Hit http://archive.ubuntu.com precise-backports/main TranslationIndex
Hit http://archive.ubuntu.com precise-backports/multiverse TranslationIndex
Hit http://archive.ubuntu.com precise-backports/restricted TranslationIndex
Get:37 http://archive.ubuntu.com precise-backports/universe TranslationIndex [72 B]
Get:38 http://archive.ubuntu.com precise-security/main Sources [12.6 kB]
Get:39 http://archive.ubuntu.com precise-security/restricted Sources [14 B]
Get:40 http://archive.ubuntu.com precise-security/universe Sources [4,522 B]
Get:41 http://archive.ubuntu.com precise-security/multiverse Sources [696 B]
Get:42 http://archive.ubuntu.com precise-security/main i386 Packages [43.9 kB]
Get:43 http://archive.ubuntu.com precise-security/restricted i386 Packages [14 B]
Get:44 http://archive.ubuntu.com precise-security/universe i386 Packages [10.3 kB]
Get:45 http://archive.ubuntu.com precise-security/multiverse i386 Packages [1,393 B]
Hit http://archive.ubuntu.com precise-security/main TranslationIndex
Hit http://archive.ubuntu.com precise-security/multiverse TranslationIndex
Hit http://archive.ubuntu.com precise-security/restricted TranslationIndex
Hit http://archive.ubuntu.com precise-security/universe TranslationIndex
Hit http://archive.ubuntu.com precise/main Translation-en
Hit http://archive.ubuntu.com precise/multiverse Translation-en
Hit http://archive.ubuntu.com precise/restricted Translation-en
Hit http://archive.ubuntu.com precise/restricted Translation-bn
Hit http://archive.ubuntu.com precise/universe Translation-en
Hit http://archive.ubuntu.com precise-updates/main Translation-en
Hit http://archive.ubuntu.com precise-updates/multiverse Translation-en
Hit http://archive.ubuntu.com precise-updates/restricted Translation-en
Hit http://archive.ubuntu.com precise-updates/universe Translation-en
Hit http://archive.ubuntu.com precise-backports/main Translation-en
Hit http://archive.ubuntu.com precise-backports/multiverse Translation-en
Hit http://archive.ubuntu.com precise-backports/restricted Translation-en
Hit http://archive.ubuntu.com precise-security/main Translation-en
Hit http://archive.ubuntu.com precise-security/multiverse Translation-en
Hit http://archive.ubuntu.com precise-security/restricted Translation-en
Hit http://archive.ubuntu.com precise-security/universe Translation-en
Fetched 12.8 MB in 11min 35s (18.4 kB/s)
W: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/precise-backports/universe/i18n/Index No Hash entry in Release file /var/lib/apt/lists/partial/archive.ubuntu.com_ubuntu_dists_precise-backports_universe_i18n_Index
E: Some index files failed to download. They have been ignored, or old ones used instead.
Best Answer
open your terminal and do this