When I run the code: "rosrun rviz rviz -d rospack find turtlebot_navigation/navrviz.vcg", the system said: " ERROR: the config file '/home/xzs/turtlebot/src/turtlebotapps/turtlebotnavigation/navrviz.vcg' is a .vcg file, which is the old rviz config format. New config files have a .rviz extension and use YAML formatting. The format changed between Fuerte and Groovy. There is not (yet) an automated conversion program.

" Some people said that I should change the ".launch" file, but I do not know where is the ".launch" file? And how to change it?