Understand for Ada can't be used without a license code. You need a limited time period license to run the product in evaluation mode. One can be obtained in the www site. A permanent license can be purchased there, too. The Understand_ada program will try to write a license file under /usr/local/share/understand_ada/license when you register it. Registration instructions: 1) Make sure that the user running Understand_ada when entering the registration code has proper permissions to create files under /usr/local/share/understand_ada/license when your register it. Understand_ada will try to create a file under this directory to save the registration information. This applies for both evaluation and permanent licenses. 2) Verify that the files created under /usr/local/share/understand_ada/license are accessible by all users who will be using Understand_ada. Usually ''chmod -R a=r+X /usr/local/share/understand_ada/license'' will do. http://www.scitools.com/