Coolwebsearch.info is a browser hijacker used to promote rogue anti-spyware programs. Coolwebsearch.info usually infiltrates the system by using trojans exploiting browser security holes. Once active, Coolwebsearch.info will change your homepage to, obviously, Coolwebsearch.info and will redirect the browser to other malicious websites, where you may get infected with additional malware. Coolwebsearch.info runs at startup and displays popups to "warn" the user of an infection, which is most certainly non-existent. This warning message comes together with a solution - a rogue anti-spyware program, which, if bought, would supposedly dispose of the problem. Coolwebsearch.info is a scam - do not trust it and block Coolwebsearch.info using your HOSTS file.

Source: http://www.2-viruses.com/remove-coolwebsearchinfo