Hi, Been using AutoCAD LT 2015 since Jan....without problems. I have a project to add engineering installation to a house I worked on before. Part of it to add external refernces of the notes and details provided by the engineer. To bring up the external refernce pallette I have always typed in the command line EX then chose external rfernces from the drop down. When I do that njow I get an error unknown command.....I can't figure out how to get the external reference pallette up.....what happened?