====== Start() function needs the [STAThread] attribute ====== The Start() function in migrated VO applications needs to have the [STAThread] attribute: [STAThread]; function Start() as void If this attribute is not set, you may experience strange crashes. As sample: when opening a printer selection dialog in an application without this attribute the application crashed. After adding the attribute, the printer selection dialog showed up correctly and the application does not crashed anymore.