@kedarp @Abrinister Thanks to both of you. Kedarp deserves a real thank for making me understand the problem, its source and its nature in depth
. Whereas Abrinister simply posted a link which made my problem solved
BTW, apart from editing /etc/apt/sources.list, I had to put my hands on /etc/apt/sources.list.d folder and manually removed some entries
. Does not sources.list and
sudo apt-get update
enough? Because when the problem solved and I ran an apt-get update, it was showing some "duplicate entries" in "var/...[whatever]" folder. I manually removed the entries from /etc/apt/sources.list.d and it worked.
Does Precise have some problems with google? I had to comment out google repos to get a result.