I run full scan several times, formated my PC twice but didn't worked nothing is working. Then I informed my situation to my cable operator, and asked if it is possible that I'm getting this virus from our LAN. They clearly said no it's not possible.
I posted my problem on a tech forum. They said I may be getting infected after visiting any infected site, or may be AVG is identifying a normal file
Someone suggest me to use Avast anitvirus so installed latest version of Avast. Now it giving me the warning of 'g.asdafdgfgf.com/ads.js' each time visiting any site.
When I goggled 'g.asdafdgfgf.com/ads.js' I found this thread.
Seems finally I've found answer of my problem and something to share with my cable operator. Just can't wait talk with them.
This thread is going to help thousands of users/operator. Thanks to everyone who contributed in this thread, specially Mr. Rohit, and Mr Anjanesh.
Regards,
Pankaj