When you initially launch the application, you will see a welcome window. This window provides an overview of the most common tasks and provides convenient links to helpful resources for more information.
Select Show this window when Nitro PDF Pro opens
if you want to see this window upon launching the application. However, you can uncheck this option if you no longer wish to see this dialog at start-up. You may elect to re-enable this setting anytime via Help > Welcome to Nitro PDF Pro.