Executable Vaccine - Version 4.0 Executable Vaccine protects your PC by acting as an executable file filter. It attaches to the operating system and filters all executable files, be it .exe .com .dll .drv .sys .dpl etc from all drives and all network shares against a list of files or paths, you, the administrator provide as trusted applications. If a prohibited executable is loaded, a customizable popup box shows up informing the user,