You must have the .NET Framework 3.5, 4.0, or newer installed first.
Managed assemblies that facilitate communication between your custom solution and the Office application. microsoft visual studio 2010 tools for office runtime -x64-
The Visual Studio Tools for Office (VSTO) Runtime is a set of components that allows Office applications like Word, Excel, PowerPoint, and Outlook to host the .NET Framework Common Language Runtime (CLR). This enables developers to create managed add-ins and document-level customizations that extend the functionality of the Office suite. The runtime includes two primary parts: You must have the
Conversely, if you have 32-bit Office installed on a 64-bit Windows system, you would actually need the x86 version of the runtime. System Requirements and Prerequisites microsoft visual studio 2010 tools for office runtime -x64-
