Where is the Configuration Management Application Block?
This is not a new topic but since this question has been asked a few times recently, here is a quick revisit:
Most of the .NET applications use configuration management and that's why the basic support for configuration management has been included in the .NET Framework from the early versions. The configuration management functionality is provided by the classes in the System.Configuration namespace in the System assembly. But the requirements for configuration management usually go beyond the basic functionality provided by these components so one had to write lots of code to meet the application requirements using the out-of-the-box functionality. This is why the patterns and practices team developed the Configuration Management Application Block.
This application block proved to be a very popular one so the .NET Framework team decided to build this functionality into the framework, beginning with the .NET Framework 2.0. As a result, the Configuration Management Application Block was removed from the Enterprise Library 2.0 and some of the helper classes and design-time components were moved to the Enterprise Library Core. Since the other application blocks were relying on the Configuration Management Application Block, they were modified to use the new components in the .NET Framework instead. You can find more information on this subject here.
The new classes providing the configuration management functionality still live in the System.Configuration namespace, but they are compiled into a separate assembly named System.Configuration. So in order to use the new bits, you need to add a reference to System.Configuration.dll.
