I am having Avira antivirus installed in my system with Windows Vista Home Premium operating system. Recently I got an alert from Avira that there is an infection of Win32.Zombie.Mistfall in the system. I cannot delete Win32.Zombie.Mistfall from the antivirus interface. I do not know the place where it has affected or else I could have manually deleted it from the system. But, I cant understand why the antivirus is not allowing me to delete Win32.Zombie.Mistfall. I need suitable suggestions to this problem, kindly help.