The command will not work. It was created before the ability to launch a script from outside the GUI. Here is the code for it if you still need it:
Code:
def quitall():
#Send '-e' flag to vizard to make it exit
path = _WIN_VIZ_PATH
#Make sure vizard_path exists
if len(path) > 0:
if path[-1] != '\\':
path += '\\'
path += 'bin\\Vizard.exe" -e'
path = '"' + path
os.system(path)
#Now quit winviz
quit()