I have a custom application based on ArcFM Viewer for ArcGIS Engine. I want to use an external GPS receiver with that application and the setup window does not let me choose a different geographic datum. In comparison the corresponding drop down field in ArcGIS Desktop has a variety of datums to choose from. Where is this list defined? How can I get this in my ArcFM Viewer application? It might also be helpful to know where ArcGIS actually gets that list from. Here are some screenshots. Sorry for the German UI.