I think after i downloaded a game online my computer got infected with a virus. This virus stopped my security center from working and its telling me to download a vista virus scan which is like 90 dollars and i cannot afford that at the moment. The virus doesn't let me do anything on the administrative account like go on the internet or get my documents but it does let me do those things in the guest account. What can i do? what can i download to get rid of this virus. btw i cannot download on the guest side of the computer since it does not have administrative power to do so. please help.