Hi
I am a C++ programmer but am having to do a small app in C#
I want to display a Message Box so wrote
Code:
MessageBox.Show("The diagram already exists - Do you want to overrite?", "Diagram Exists",
         MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
But the compiler says
C:\VSProjects\Addin2\Class1.cs(180,29): error CS0103: The name 'MessageBox' does not exist in the current context

How can I fix this?

Graham