In the development of applications, we may need to develop Office's plugins. In VS2003, we easily develop an add-in, using COM Add-in, add a menu or toolbar button on the Office system software.
Complete program reference:
How to build an office com address-in by Using Visual C # .NET
http://support.microsoft.com/?kbid=302901
If you want to better control Outlook in the program, for example, get all messages, all contacts, emails, control mail, mail statistics. Integrate our application and Outlook integration, etc., you can refer to:
An Introduction to Programming Outlook 2003 Using C #
What's new in Microsoft Office Outlook 2003 For Developers?
http://techedbloggers.net/topics/office/outlook.category
I believe that after reading the above article, you will have a comprehensive understanding of Outlook!