Don't worry about free antivirus i am here with some of the free antivirus and its link from where you can download and then install.
Try to visit and then download.
1. AVG 8.
2. Avast.
3. Free-av.
4. Avira Antivir Personal
5. PC Tool etc.
http://www.pctools.com/free-antivirus/
http://www.avg.com/
http://www.avast.com/eng/download-avast-home.html
http://www.free-av.com/en/download/1/avira_antivir_personal__free_antivirus.html
for more details and support you can contact. http://www.iyogi.co.uk
PRINCE
June 2009