Lately I've encountered a rather weird behavior when using .NET 2.0's configuration model. Let's say I have the following custom configuration section: public class TestConfigSection: ConfigurationSection { public TestConfigSection() { } public TestConfigSection( string testAttrib) { TestAttrib = testAttrib; } [ConfigurationProperty( " testAttrib " , IsRequired = true )] public String TestAttrib { get { return (String) this [ " testAttrib " ]; } set { this [ " testAttrib...