Outlook Development Support Now you can develop managed add-ins for Outlook. Visual Studio 2005 Tools for Office includes both design-time and run-time support for building application-level add-ins for Outlook using managed code. Visual Studio project templates help you build Outlook add-ins and add-in setup projects. When you create an Outlook add-in, the primary class represents the Outlook application because the add-in operates at the application level rather than at the document level. A dedicated add-in loader component (AddinLoader) creates a separate AppDomain for each add-in, enforces strict security policy, and unloads the add-in when it is disconnected. The AddinLoader component provides a single, consistent mechanism for loading both document-level customizations and application-level add-ins into Office applications. Both Visual Basic and Visual C# provide a new Outlook Add-in project type to get you started. Create managed application-level add-ins for Outlook using Visual C# or Visual Basic