I just started learning AutoCAD 2013, tried to model a tank and after a day of work the turret disappeared with all its details, and it's only visible when I rotate the whole model, without being able to interact with the non visible piece in any way. Is there any way I can recover the missing object, or at least permanently delete it and remake it afterwards?
comparison picture.jpg Here is the .dwg that I worked on: Panther ausf g.dwg