Adding new Apps to server

The company I work for had the previous employee add more apps to the box. He did not tell where they are located or how to add more apps. Does anyone know how to do this?

Are you sure that this server is running Mail-in-a-Box at all? I’m asking because the interface shown on your screenshot is either a completely different product or it could be a custom-built interface to manage additional resources on the box… Either way, this isn’t something anyone here is likely to be able to help with.