Click the Files of Type menu and see all the different files that you can open directly in Navisworks. What we're interested in right now is to open an AutoCAD drawing file. So go to autodesk.dwgdxf. And you'll see a drawing file in this directory. It's an underground communication system. Click on Open. Now that the files in here, we can pan around and zoom on it as we see fit. Now, what happens is, when Navisworks opens this, it makes a Navisworks cache file and puts it in the directory.