During the development stage of your project, to access the object model of any OLE Automation server applications, you must have a copy of the appropriate application program installed on the computer you are developing the OLE Automation controller with.
Equally, during CitectSCADA runtime, there must be a copy of the appropriate application program installed on the computer you are running the OLE Automation controller from. If, for example, you were calling the code which creates the object from say a button on a graphics page on a CitectSCADA Client machine, the appropriate application program must be installed on every Client machine with access to that graphics page, for the code to work (if called) on that Client machine.
All of the Microsoft Office suite of products support the VBA language in some manner, and export an OLE Automation object type library which you can view and use. See How to view an OLE Automation object type library from a Microsoft Office product.
Also, the VB programming IDE within Visual Studio can be referenced to load the appropriate type library as required. See How to view an OLE Automation object type library in VB.
Both these suites provide an object browser which you can use to explore the object models. You use the structure of the object model to access, manipulate and control the OLE Automation object using CitectVBA. See Understanding object models in OLE Automation.
OLE automation objects