Hey all. :-\
I have been trying to put up with Avast blasting my ears with DUN DUN DUN THREAT HAS BEEN DETECTED for 2 months now.
Here’s the thing.
Everytime I open up Firefox, 30 seconds later Avast always tells me that a threat has been detected and blocked.
Here is an image of what normally shows up.
http://i1288.photobucket.com/albums/b486/sirskrill/virus_zpswfhzy2ti.png
It’s getting on my nerves how every time I open up Firefox, Avast always yells at me. 
Apparently it’s called “media.fastclick.net” or something. I’ve tried looking stuff up about it and the only things that come up are long and confusing ways to remove it, which don’t even work. I’ve tried scanning for it with Avast and nothing comes up. Can someone please help me remove it because I CANNOT PUT UP WITH IT ANY LONGER! :‘( :’( 
Here is an image of the details of the threat.
http://i1288.photobucket.com/albums/b486/sirskrill/virus2_zps2ahycr3s.png