It might be a variant of a horrible Russian ad-program called "Coolwebsearch" Go here:
http://www.spywareinfo.com/~merijn/downloads.html
This is a quick bunch.
It is an awful little bug. I used the remover 10 times it seemed like and my computer still had not removed it.
Why? I WASN'T IN SAFE MODE.
If you have problems removing stuff in regular mode, reboot in safemode and run cwshredder or some other program again.
It helps a ton...