There is only one file type that uses the .ADE extension:
Access Project Extension
Database project file created by Microsoft Access, a desktop database program; contains all data saved in a .ADP project, except the modules written in the Visual Basic for Applications (VBA) programming language are compiled and the source code is removed.
ADE files are also compressed so that they reduce the file size and optimize performance in Access. Even with the file compression and source code compilation, all database components in an ADE file behave in the same manner as the existing ADP project file.
NOTE: ADE projects help protect proprietary VBA source code by disallowing the original source code to be viewed or edited.
Updated: January 22, 2011