Is there a way to store an object of a user defined type in the applications
settings?

I have compiled the type in a dll and referenced the dll into my
application.
I have applied the [Serializable] attribute to my user defined type.
I can create a settings property of the correct type, but it won't serialize
(or won't deserialize).

Example:

public class State
{
   bool b1;
   string s1;
   int n1;

   public State(bool b, string s, int n)
   {
       b1=b; s1=s; n1=1;
   }
}

public void TestStateSetting()
{
   Settings.Default.MyState = new State(true, "Hi", 0);
   Settings.Default.MyString = "System.string serializes ok";

   // Save and reload settings to simulate program shutdown and restart.
   Settings.Default.Save();
   Settings.Default.Reload();

   // Primitive types work but user defined (and other system types) don't
work.
   MessageBox.Show("Settings.Default.MyState == null !!");
   MessageBox.Show("Settings.Default.MyString == 'System.string serializes
ok'");
}