I need to develop an application which will has the capability to send emails using C# with visual studio. The app will be able to use templates for mail, and a lot of thing
I think you need to run that .msi to install the dlls. After I ran that .msi I can go to (VS 2012) Add References > Assemblies > Extensions and all of the Microsoft.Office.Interop dlls are there.
On my computer the dlls are found in "c:\Program Files(x86)\Microsoft Visual Studio 12.0\Visual Studio Tools for Office\PIA" so you could check in a similar/equivalent directory on yours just to make sure they're not there?