"apt-get update" always failed to fetch

Question

I don't understand why this issue could be survive. It display this error message all the time

Fetched 32.8 MB in 1min 16s (430 kB/s)                                         
W: Failed to fetch http://security.ubuntu.com/ubuntu/dists/trusty-security/main/binary-amd64/Packages  Hash Sum mismatch

W: Failed to fetch http://security.ubuntu.com/ubuntu/dists/trusty-security/universe/binary-i386/Packages  Hash Sum mismatch

E: Some index files failed to download. They have been ignored, or old ones used instead.

I was tried to using these commands (which found in this question)

sudo apt-get clean
sudo rm -vf /var/lib/apt/lists/*
sudo rm -vf /var/lib/apt/lists/partial/*
sudo apt-get update

No luck for me. That dump message show up again. Always failed with security.ubuntu.com. My internet connection is OK, I'm able to ping to security.ubuntu.com without any trouble.

So, the question here is why? And anyone out there can help me out of this? I'm going to crazy!

Answer 1

Configure your proxy in network settings of your PC for each of items like HTTP, HTTPS, FTP and Socks and apply settings to system wide if you are using proxy.

Remove the existing packages and then try as follows:

apt-get clean
rm -rf /var/lib/apt/lists/*
apt-get clean
apt-get update 
apt-get upgrade

(copied from above message)

Answer 2

This worked for me:

 apt-get clean
 rm -rf /var/lib/apt/lists/*
 apt-get clean
 apt-get update 
 apt-get upgrade

Answer 3

I have Ubuntu 14.04 LTS, and sometimes when I use this command, I encounter with this problem. For solving this you can use the following way:

1. please go to system settings.

   

2. click on software & updates

   

3. go to other software section. You can find the links that are relative to this error. Uncheck the relative links and click close. If you can't find relative link you can go to ubuntu software section and uncheck options that may can relative to this error. Sometimes with changing Download Server to Main Server your problem can be solved. For changing download server you can go to ubuntu software section and change Download From and choose Main Server.

Answer 4

Please navigate to

/etc/apt

then open the sources.list file

sudo -H gedit sources.list

then remove the broken or unavailable package link and save.

Then add a valid one.

Answer 5

I had a similar problem a week or two ago, and it turned out to be a DNS problem. I edited my static configuration in /etc/network/interfaces and changed the DNS entry to Googles DNS with:

dns-nameserver 8.8.8.8 

Then rebooted.

Answer 6

This worked for me:

1. Open "Software & Updates" by launching that application or by running this in the command-line:

   software-properties-gtk
   

   

2. Make all four checkboxes are ticked (main, universe, restricted, multiverse), unless you don't want all four sources of software

3. Change the server in control labelled "Download from:" to something else. For some reason, making a change forces APT to refresh the software database in a way that works.

4. Close, and click "Reload" when prompted.

If you prefer, instead of clicking "Reload", you can run this on the command-line:

sudo apt update