Can't add new sections into app.config

Each time I try to add a very basic section into app.config I get the following error:

Configuration system failed to initialize.

I have looked at the variety of articles but none of those has helped so far. Any ideas what is going wrong?

Edit:

  <configSec开发者_JS百科tions>
    <section name="Test" type="TestType"/>
  </configSections>

  <Test>  

  </Test>

Do you define a configuration section handler? Here is a tutorial:

http://support.microsoft.com/kb/309045

Edit: (Based on your updated question) I recommend to specify the type with the fully qualified assembly name.

Read/Write App.config with .NET 2.0/Enterprise http://geekswithblogs.net/akraus1/articles/64871.aspx