Add-in Express .NET is the first visual tool for programming Microsoft Office extensions, including COM add-ins, smart tags, RTD servers and Microsoft Excel user defined functions. It completely supports Microsoft Visual Studio .NET (2003, 2005, 2008) and makes it very comfortable for developing extensions for all available Microsoft Office versions from 2000 to 2007.
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Create COM add-in / plugin in VB.NET, C#, C++ for Office 2007 - 2000