Why after fresh Ubuntu 12.04 installation update aren't being installed?

My problem is solved now. I'm posting here the solution step by step. From the output of sudo apt-get update, I was facing following problem:

W: Failed to fetch gzip:/var/lib/apt/lists/partial/us.archive.ubuntu.com_ubuntu_dists_precise-updates_multiverse_binary-i386_Packages  Hash Sum mismatch

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

To solve this problem I entered the following commands one by one.

sudo rm /var/lib/apt/lists/* -vf
sudo apt-get clean
sudo apt-get autoremove
sudo apt-get update
sudo apt-get dist-upgrade 

Then the output was

audity@auditypc:~$ sudo rm /var/lib/apt/lists/* -vf
[sudo] password for audity: 
removed `/var/lib/apt/lists/archive.canonical.com_ubuntu_dists_precise_partner_binary-i386_Packages'
removed `/var/lib/apt/lists/archive.canonical.com_ubuntu_dists_precise_Release'
removed `/var/lib/apt/lists/archive.canonical.com_ubuntu_dists_precise_Release.gpg'
removed `/var/lib/apt/lists/dl.google.com_linux_talkplugin_deb_dists_stable_main_binary-i386_Packages'
removed `/var/lib/apt/lists/dl.google.com_linux_talkplugin_deb_dists_stable_Release'
removed `/var/lib/apt/lists/dl.google.com_linux_talkplugin_deb_dists_stable_Release.gpg'
removed `/var/lib/apt/lists/extras.ubuntu.com_ubuntu_dists_precise_main_binary-i386_Packages'
removed `/var/lib/apt/lists/extras.ubuntu.com_ubuntu_dists_precise_main_source_Sources'
removed `/var/lib/apt/lists/extras.ubuntu.com_ubuntu_dists_precise_Release'
removed `/var/lib/apt/lists/extras.ubuntu.com_ubuntu_dists_precise_Release.gpg'
removed `/var/lib/apt/lists/lock'
rm: cannot remove `/var/lib/apt/lists/partial': Is a directory
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-backports_main_binary-i386_Packages'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-backports_main_i18n_Index'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-backports_main_i18n_Translation-en'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-backports_main_source_Sources'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-backports_multiverse_binary-i386_Packages'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-backports_multiverse_i18n_Index'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-backports_multiverse_i18n_Translation-en'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-backports_multiverse_source_Sources'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-backports_Release'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-backports_Release.gpg'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-backports_restricted_binary-i386_Packages'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-backports_restricted_i18n_Index'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-backports_restricted_i18n_Translation-en'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-backports_restricted_source_Sources'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-backports_universe_binary-i386_Packages'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-backports_universe_i18n_Index'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-backports_universe_i18n_Translation-en'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-backports_universe_source_Sources'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise_main_binary-i386_Packages'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise_main_i18n_Index'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise_main_i18n_Translation-en'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise_main_source_Sources'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise_multiverse_binary-i386_Packages'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise_multiverse_i18n_Index'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise_multiverse_i18n_Translation-en'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise_multiverse_source_Sources'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise_Release'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise_Release.gpg'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise_restricted_binary-i386_Packages'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise_restricted_i18n_Index'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise_restricted_i18n_Translation-en'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise_restricted_source_Sources'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-security_main_binary-i386_Packages'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-security_main_i18n_Index'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-security_main_i18n_Translation-en'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-security_main_source_Sources'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-security_multiverse_binary-i386_Packages'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-security_multiverse_i18n_Index'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-security_multiverse_i18n_Translation-en'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-security_multiverse_source_Sources'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-security_Release'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-security_Release.gpg'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-security_restricted_binary-i386_Packages'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-security_restricted_i18n_Index'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-security_restricted_i18n_Translation-en'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-security_restricted_source_Sources'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-security_universe_binary-i386_Packages'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-security_universe_i18n_Index'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-security_universe_i18n_Translation-en'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-security_universe_source_Sources'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise_universe_binary-i386_Packages'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise_universe_i18n_Index'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise_universe_i18n_Translation-en'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise_universe_source_Sources'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-updates_main_binary-i386_Packages'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-updates_main_i18n_Index'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-updates_main_i18n_Translation-en'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-updates_main_source_Sources'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-updates_multiverse_binary-i386_Packages'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-updates_multiverse_i18n_Index'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-updates_multiverse_i18n_Translation-en'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-updates_multiverse_source_Sources'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-updates_Release'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-updates_Release.gpg'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-updates_restricted_binary-i386_Packages'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-updates_restricted_i18n_Index'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-updates_restricted_i18n_Translation-en'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-updates_restricted_source_Sources'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-updates_universe_binary-i386_Packages'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-updates_universe_i18n_Index'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-updates_universe_i18n_Translation-en'
removed `/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-updates_universe_source_Sources'
audity@auditypc:~$ sudo apt-get clean
[sudo] password for audity: 
audity@auditypc:~$ sudo apt-get autoremove
Reading package lists... Done
Building dependency tree       
Reading state information... Done
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
audity@auditypc:~$ sudo apt-get update
Get:1 http://dl.google.com stable Release.gpg [198 B]                          
Get:2 http://us.archive.ubuntu.com precise Release.gpg [198 B]                 
Get:3 http://dl.google.com stable Release [1,347 B]                            
Get:4 http://extras.ubuntu.com precise Release.gpg [72 B]                      
Get:5 http://archive.canonical.com precise Release.gpg [198 B]                 
Get:6 http://dl.google.com stable/main i386 Packages [763 B]                   
Get:7 http://us.archive.ubuntu.com precise-updates Release.gpg [198 B]         
Get:8 http://extras.ubuntu.com precise Release [11.9 kB]                       
Ign http://dl.google.com stable/main TranslationIndex                          
Get:9 http://archive.canonical.com precise Release [7,078 B]                   
Get:10 http://extras.ubuntu.com precise/main Sources [8,130 B]                 
Get:11 http://us.archive.ubuntu.com precise-backports Release.gpg [198 B]      
Get:12 http://archive.canonical.com precise/partner i386 Packages [8,261 B]    
Get:13 http://extras.ubuntu.com precise/main i386 Packages [10.8 kB]           
Ign http://archive.canonical.com precise/partner TranslationIndex              
Get:14 http://us.archive.ubuntu.com precise-security Release.gpg [198 B]       
Ign http://extras.ubuntu.com precise/main TranslationIndex                     
Get:15 http://us.archive.ubuntu.com precise Release [49.6 kB]                  
Ign http://dl.google.com stable/main Translation-en_US                         
Get:16 http://us.archive.ubuntu.com precise Release [49.6 kB]                  
Ign http://dl.google.com stable/main Translation-en                            
Get:17 http://us.archive.ubuntu.com precise-updates Release [49.6 kB]          
Ign http://extras.ubuntu.com precise/main Translation-en_US                    
Ign http://archive.canonical.com precise/partner Translation-en_US             
Get:18 http://us.archive.ubuntu.com precise-updates Release [49.6 kB]          
Ign http://extras.ubuntu.com precise/main Translation-en                       
Ign http://archive.canonical.com precise/partner Translation-en                
Get:19 http://us.archive.ubuntu.com precise-backports Release [49.6 kB]        
Get:20 http://us.archive.ubuntu.com precise-backports Release [49.6 kB]        
Get:21 http://us.archive.ubuntu.com precise-backports Release [49.6 kB]        
Ign http://us.archive.ubuntu.com precise-backports Release                     
E: GPG error: http://us.archive.ubuntu.com precise-backports Release: The following signatures were invalid: NODATA 2
audity@auditypc:~$

Now I was facing a GPG error. To solve this I tried the following

$ sudo -i
# apt-get clean
# cd /var/lib/apt
# mv lists lists.old
# mkdir -p lists/partial
# apt-get clean
# apt-get update
# exit

After this command. I entered the final commands.

sudo apt-get dist-upgrade

Just had the US archive package list hash sum mismatch on some fresh 12.04.5 installs. Shorter solution that worked for me at least:

# rm /var/lib/apt/lists/partial/us.archive.ubuntu.com_ubuntu_dists_precise_*
# rm /var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise*
# aptitude update
... now worked ...