It's probably a browser helper object (BHO) that you accidentally installed. You can certainly try spybot s&d first, but if that doesn't work, you'll probably need to try and figure out what to disable using hijackthis:

http://www.trendsecure.com/portal/en...ols/hijackthis

Most likely the malware is installed as BHO (browser helper object) in IE.

I would try spybot s&d first. Don't bother innoculating or doing anything but a registry backup and system scan, then look at the results. Close IE before installing/running spybot s&d. Typically, you can let it fix anything it wants to fix.

If that doesn't work, you're going to need to run hijackthis and you'll need help analyzing the output. The Spybot S&D Forum is a good place for doing that.

Sybot S&D Home page: http://www.safer-networking.org/index2.html

-David