The process of creating an add-in has been moved from the previous version's Tools/Make Add-in command to the current version's File/Save As command. When you change the File Type to "Microsoft Excel Add-In (*.xla)" your file will be saved as an add-in. This sets the IsAddin property of the Workbook object to True and then saves the file. Unlike in Microsoft Excel 5/95 VBA, however, this does not compile your VBA code, nor does it protect the VBA project. See the section titled "Code Cleaning" for details on compiling your project.