I'm not sure exactly what happened either... when you add a new SF winforms app, the template for that line of code looks like this:e.Forms.Add(typeof($safeprojectname$.Form1));
So, the project name (which is the default namespace) would be put first, and then the text "Form1" would be put. Since "Form1" is not anywhere to be seen in the code that you posted, I can only assume that the line was modified by hand after the project was created, or that the C# refactor tool failed to properly rename the form from Form1 to MainForm.