EXP 3: Cannot update some packages from Debian 7.5

Problem
Cannot update some official packages when fresh install Debian 7.5

Cause
Maybe default repositories are not enough.

Solution
nano /etc/apt/sources.list

Add following repositories into sources.list file:

deb http://ftp.debian.org/debian/ wheezy main
deb-src http://ftp.debian.org/debian/ wheezy main
deb http://security.debian.org/ wheezy/updates main
deb-src http://security.debian.org/ wheezy/updates main
deb http://ftp.debian.org/debian/ wheezy-updates main
deb-src http://ftp.debian.org/debian/ wheezy-updates main


Save file, and update repos again.

apt-get update