You can use Microsoft Visual Basic for Applications in any Microsoft Office application to control Microsoft Outlook. For example, if you are developing a cross-application solution using one primary application and several secondary applications, you can write Visual Basic for Applications code in the primary application to automate Outlook to send messages and to store and retrieve information in Outlook items. For example, in Microsoft Excel you can write routines that send a workbook to an Outlook distribution list.
To control Outlook objects from outside Outlook, you must establish a reference to the Outlook object library from the project in which you are writing code. To do this, use the References dialog box in the Visual Basic Editor in the primary application. You can then write code that returns a reference to the Outlook Application object. Through this reference, your code has access to all the objects, properties, methods, and constants defined in the Outlook type library.
There are several ways to return a reference to the Outlook Application object:
Automating Outlook from a Visual Basic Application provides examples of using these methods of referencing the Outlook Application object.