download avast go to the avast website which is www.avast.com it is one of the best products ever and try to download avast antivirus home edition its completly free ands its one of the best antivirus in the world it includes
Anti-spyware built-in Web Shield
Anti-rootkit built-in Automatic updates
Strong self-protection Virus Chest
Antivirus kernel System integration
Simple User Interface Integrated Virus Cleaner
Resident protection Support for 64-bit Windows
P2P and IM Shields Internationalization
Network Shield if you get avast on your computer youll wipe out that virus because FREE avast! antivirus Home Edition includes ANTI-SPYWARE protection, certified by the West Coast Labs Checkmark process, and ANTI-ROOTKIT detection based on the best-in class GMER technology. No additional purchase is required.
Simple to use and automated Daily automatic updates ensure continuous data protection against all types of malware and spyware. Simply install and forget. We've made avast! as simple to use as possible.
Tried and Trusted With over 70 million users of avast!, you can rest assured that you are using one of the most tried and trusted products in Windows security. We support more Windows versions (from Windows 95 to Vista 64bit) than any other anti-malware product. No matter what system you have, avast! has it covered.
if the trojan thing doesent let you download it off the site go to places like download.com and search avast home edition this is a must if you want to get rid of that virus and if that doesent work im really not sure what to do exept reformatt(clears your disk of all data). download avast home edition heres the link http://avast.com/eng/avast_4_home.html