Did your computer ever infected by some new Viruses, Trojans or other threats even you had installed an Anti-Virus program? Did you have no idea which installation files are "good" and which are "bad" when you rebuild your system after a big Viruses explosion? Did you know even the files are disinfected, they are still permanently modified? (For example, the virus codes are removed, but blanks are left. They probably can't be executed properly after disinfected.)
