Help Computer infected - asked before, but I already have Ad Aware, AVG, Norton and Avast.?

I keep getting an annoying pop up every time I try to open my brouser or go to a different website. It says "your computer was infected by trojan, It's dangerous for your computer, some files can be lost! Click ok to download the antispyware program to protect your computer"

Of course I click cancel, but it continues to pop up every time I try to go to a web page. Please help!

I already have anti spywear and antivirus protection. I have AVG, Norton anti spywear protection, Avast and Ad Aware

Help Computer infected - asked before, but I already have Ad Aware, AVG, Norton and Avast.?hijackthis

Phony warnings or pop-ups about a virus infection and the attempt to sell you some useless software to "fix" the problem usually indicates a Smitfraud infection. DO NOT BUY THE PRODUCT THEY TRY TO SELL YOU!

Sounds like your computer may have a variant of this ubiquitous Smitfraud infection. Almost all "general purpose","all-in one" spyware and virus removal programs such as AVG, Norton, or Spybot S %26 D cannot remove it compleatly.

Free specialised Smitfraud removal tool is here (SmitfraudFix)

http://siri.urz.free.fr/Fix/SmitfraudFix...

Good luck.

Help Computer infected - asked before, but I already have Ad Aware, AVG, Norton and Avast.?malware