Make sure your repository is correct and if you have firewall, your port 80 (http) and port 53 (dns) is open.
taufanlubis@zyrex:~$ cat /etc/apt/sources.list
## Repository from Main Server
deb http://archive.ubuntu.com/ubuntu/ feisty main universe multiverse restricted
deb-src http://archive.ubuntu.com/ubuntu/ feisty main universe multiverse restricted #Added by software-properties
deb http://security.ubuntu.com/ubuntu/ feisty-security universe main multiverse restricted
deb-src http://security.ubuntu.com/ubuntu/ feisty-security universe main multiverse restricted #Added by software-properties
deb http://archive.ubuntu.com/ubuntu/ feisty-updates universe main multiverse restricted
deb-src http://archive.ubuntu.com/ubuntu/ feisty-updates universe main multiverse restricted #Added by software-properties
deb http://archive.ubuntu.com/ubuntu/ feisty-proposed universe main multiverse restricted
deb-src http://archive.ubuntu.com/ubuntu/ feisty-proposed universe main multiverse restricted #Added by software-properties
deb http://archive.ubuntu.com/ubuntu/ feisty-backports universe main multiverse restricted
deb-src http://archive.ubuntu.com/ubuntu/ feisty-backports universe main multiverse restricted #Added by software-properties
First, update your repository list.
taufanlubis@zyrex:~$ sudo apt-get update
Password:
Get:1 http://security.ubuntu.com feisty-security Release.gpg [191B]
Ign http://security.ubuntu.com feisty-security/universe Translation-en_US
Get:2 http://archive.ubuntu.com feisty Release.gpg [191B]
Ign http://archive.ubuntu.com feisty/main Translation-en_US
Ign http://security.ubuntu.com feisty-security/main Translation-en_US
Ign http://security.ubuntu.com feisty-security/multiverse Translation-en_US
Ign http://security.ubuntu.com feisty-security/restricted Translation-en_US
Hit http://security.ubuntu.com feisty-security Release
Ign http://archive.ubuntu.com feisty/universe Translation-en_US
Ign http://archive.ubuntu.com feisty/multiverse Translation-en_US
Ign http://archive.ubuntu.com feisty/restricted Translation-en_US
Get:3 http://archive.ubuntu.com feisty-updates Release.gpg [191B]
Ign http://archive.ubuntu.com feisty-updates/universe Translation-en_US
Ign http://archive.ubuntu.com feisty-updates/main Translation-en_US
Ign http://archive.ubuntu.com feisty-updates/multiverse Translation-en_US
Ign http://archive.ubuntu.com feisty-updates/restricted Translation-en_US
Get:4 http://archive.ubuntu.com feisty-proposed Release.gpg [191B]
Hit http://security.ubuntu.com feisty-security/universe Packages
Ign http://archive.ubuntu.com feisty-proposed/universe Translation-en_US
Ign http://archive.ubuntu.com feisty-proposed/main Translation-en_US
Hit http://security.ubuntu.com feisty-security/main Packages
Hit http://security.ubuntu.com feisty-security/multiverse Packages
Hit http://security.ubuntu.com feisty-security/restricted Packages
Ign http://archive.ubuntu.com feisty-proposed/multiverse Translation-en_US
Ign http://archive.ubuntu.com feisty-proposed/restricted Translation-en_US
Get:5 http://archive.ubuntu.com feisty-backports Release.gpg [191B]
Ign http://archive.ubuntu.com feisty-backports/universe Translation-en_US
Ign http://archive.ubuntu.com feisty-backports/main Translation-en_US
Ign http://archive.ubuntu.com feisty-backports/multiverse Translation-en_US
Ign http://archive.ubuntu.com feisty-backports/restricted Translation-en_US
Hit http://archive.ubuntu.com feisty Release
Hit http://security.ubuntu.com feisty-security/universe Sources
Hit http://security.ubuntu.com feisty-security/main Sources
Hit http://security.ubuntu.com feisty-security/multiverse Sources
Hit http://security.ubuntu.com feisty-security/restricted Sources
Hit http://archive.ubuntu.com feisty-updates Release
Hit http://archive.ubuntu.com feisty-proposed Release
Hit http://archive.ubuntu.com feisty-backports Release
Hit http://archive.ubuntu.com feisty/main Packages
Hit http://archive.ubuntu.com feisty/universe Packages
Hit http://archive.ubuntu.com feisty/multiverse Packages
Hit http://archive.ubuntu.com feisty/restricted Packages
Hit http://archive.ubuntu.com feisty/main Sources
Hit http://archive.ubuntu.com feisty/universe Sources
Hit http://archive.ubuntu.com feisty/multiverse Sources
Hit http://archive.ubuntu.com feisty/restricted Sources
Hit http://archive.ubuntu.com feisty-updates/universe Packages
Hit http://archive.ubuntu.com feisty-updates/main Packages
Hit http://archive.ubuntu.com feisty-updates/multiverse Packages
Hit http://archive.ubuntu.com feisty-updates/restricted Packages
Hit http://archive.ubuntu.com feisty-updates/universe Sources
Hit http://archive.ubuntu.com feisty-updates/main Sources
Hit http://archive.ubuntu.com feisty-updates/multiverse Sources
Hit http://archive.ubuntu.com feisty-updates/restricted Sources
Hit http://archive.ubuntu.com feisty-proposed/universe Packages
Hit http://archive.ubuntu.com feisty-proposed/main Packages
Hit http://archive.ubuntu.com feisty-proposed/multiverse Packages
Hit http://archive.ubuntu.com feisty-proposed/restricted Packages
Hit http://archive.ubuntu.com feisty-proposed/universe Sources
Hit http://archive.ubuntu.com feisty-proposed/main Sources
Hit http://archive.ubuntu.com feisty-proposed/multiverse Sources
Hit http://archive.ubuntu.com feisty-proposed/restricted Sources
Hit http://archive.ubuntu.com feisty-backports/universe Packages
Hit http://archive.ubuntu.com feisty-backports/main Packages
Hit http://archive.ubuntu.com feisty-backports/multiverse Packages
Hit http://archive.ubuntu.com feisty-backports/restricted Packages
Hit http://archive.ubuntu.com feisty-backports/universe Sources
Hit http://archive.ubuntu.com feisty-backports/main Sources
Hit http://archive.ubuntu.com feisty-backports/multiverse Sources
Hit http://archive.ubuntu.com feisty-backports/restricted Sources
Fetched 5B in 4s (1B/s)
Reading package lists… Done
Second, upgrade all your installed applications.
taufanlubis@zyrex:~$ sudo apt-get upgrade
Reading package lists… Done
Building dependency tree
Reading state information… Done
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
Third, upgrade your distro.
taufanlubis@zyrex:~$ sudo apt-get dist-upgrade
Reading package lists… Done
Building dependency tree
Reading state information… Done
Calculating upgrade… Done
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
taufanlubis@zyrex:~$
Now, all your installed applications and distro have already updated.
Taufan Lubis - Ubuntu Linux 