OnGuard is a library of components, classes, and routines that allow you to protect your applications after they are released to the public. Using OnGuard, you could release an application that is partially functional so that users can try it. When a user is ready to purchase the fully functional application, you supply a release code to unlock all of the features (or the subset that the user is purchasing). You can make your application readily available to a large number of potential users, but still protect your investment. Application protection is accomplished through the use of keys to lock or restrict one or more features of an application and several types of release codes (or access codes) to enable them.