How to: Install Outlook Primary Interop Assemblies

To call Outlook from managed code you need to have the Outlook Interop Assembly which is on the Office disk. Make sure you have .NET already installed because:

The .NET Programmability Support options only appear if Microsoft .NET Framework 1.1 is already installed on the computer.

And you'll want the Framework for the CLR (the engine that runs managed code) and for the C# compiler to convert your text into managed code.