I would download and install Malwarebytes anti-malware. It's free and it's removed anything I've ever had on my computer. Some sites will also provide a downloadable file that can wipe the virus, it depends on what it is. If Malwarebytes doesn't work, come back and we'll try something else. Install it, run a full scan, and see what it pulls up.
http://www.malwarebytes.org/mbam.php