How to change mirrors in Ubuntu server from regional to main (source.list)

Problem:

sudo apt-get update
W: Failed to fetch http://sg.archive.ubuntu.com/ubuntu/dists/precise-backports/multiverse/binary-i386/Packages 404 Not Found

 

Solution:

sudo nano /etc/apt/sources.list

Repalce

http://xxx.archive.ubuntu.com/ubuntu

with below for all

http://archive.ubuntu.com/ubuntu