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After installing Ubuntu 12.04 I was trying to install Kile in order to edit .tex files. But this message showed up on attempting to install Kile and Updates:

W:Failed to fetch
Hash Sum mismatch , E:Some index files failed to download. They have been ignored, or old ones used instead

Now I can't install any software at all. What can I do?


I have done which you said . But now I'm trying to install Okular but this is showing :-(

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This should fix it:

From the post above:

Remove the files with

sudo rm -R /var/lib/apt/lists/partial/*

then run

sudo apt-get update && sudo apt-get upgrade

If it doesn't work, try this:

sudo rm -rf `find /var/lib/apt/lists/ | grep -v gpg`

EDIT: Okay, try this:

sudo fuser -vvv /var/lib/dpkg/lock
sudo rm /var/lib/apt/lists/lock
sudo cp -arf /var/lib/dpkg /var/lib/dpkg.backup
sudo cp /var/lib/dpkg/status-old /var/lib/dpkg/status
sudo cp /var/lib/dpkg/available-old /var/lib/dpkg/available
sudo rm -rf /var/lib/dpkg/updates/*
sudo rm -rf /var/lib/apt/lists
sudo rm /var/cache/apt/*.bin
sudo mkdir /var/lib/apt/lists
sudo mkdir /var/lib/apt/lists/partial
LANG=C;sudo apt-get clean
LANG=C;sudo apt-get autoclean
LANG=C;sudo apt-get --purge autoremove
LANG=C;sudo apt-get update -o APT::Cache-Limit=25165824
sudo dpkg --clear-avail
sudo dpkg --configure -a
LANG=C;sudo apt-get -f install
LANG=C;sudo apt-get --fix-missing install
LANG=C;sudo apt-get update -o APT::Cache-Limit=25165824 && sudo apt-get dist-upgrade


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Please check my editing on the post . – QFT dreamer Jan 1 '13 at 7:05
Okay, see my editing on my answer :) – MiJyn Jan 3 '13 at 19:52

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