Get the latest Windows Application Compatibility Toolkit 4.0 located at:

The first questions that many customers ask once they decide to deploy Windows XP with Service Pack 2 (SP2) are whether their existing applications are compatible and how expensive it will be to determine if they are. The Application Compatibility Toolkit (ACT) 4.0 was designed to help IT Professionals minimize the risks associated with changes to the operating system and to deploy Windows XP SP2 quickly so they can realize the value of the investments Microsoft has made in securing the desktop from threats such as viruses, worms, and spyware.