Its tha "cool-web-search" bug
Goto
www.spywareinfo.com and read hpw to remove it
1 - download and install
CWShredder | Written by Merijn specifically to search out and destroy all known mutations of the CWS trojan.
http://www.merijn.org/files/cwshredder.zip
2 - reboot
3 - download and install + run
http://www.lavasoft.de/
Ad-aware | With its ability to comprehensively scan your memory, registry, hard, removable and optical drives for known datamining, aggressive advertising, and tracking components, Ad-aware will provide the user with the confidence to surf the Internet knowing that their privacy will remain intact.