The settings and files used to build an application can be stored in a project file, and then later used to rebuild an application file. 
Note: The Visual LISP IDE is available on Windows only. 
- In Visual LISP, click Project 
 Open Project.  
- In the Enter Project Name dialog box, click Browse. 
 
- In the Open Project dialog box, select the project (PRJ) file you want to open. Click Open. 
 
- In the Project window, double-click the AutoLISP source file you want to edit. 
Note: If the Multiple Selection option is enabled, you cannot double-click an AutoLISP source file to edit it. In the Project window, right-click a file in the list, and click Multiple Selection to disable the option.