Error : The method or operation is not implemented.

Question

Hey, I am getting an error message with my program
The method or operation is not implemented.

The error is coming from this piece of code:

private static changepassword changepassword
{
get { throw new NotImplementedException(); }
}


On the form load I have the code:
if (changepassword != null)
{
changepassword.Show();
}


This message started when I was playing around with a Class Diagram to make it easier to use the objects in different forms (If that helps) and I am using Visual Studio 2008.
If anyone can help would be great
Thanks!