A startup form has not been specified
The application uses the WindowsFormsApplicationBase class but does not specify the startup form.
This can occur if the Enable application framework check box is selected in the project designer but the Startup form is not specified. For more information, see Application Page, Project Designer (Visual Basic).
To correct this error
Specify a startup object for the application.
For more information, see How to: Change the Startup Object for an Application (Visual Basic).