title: Microsoft.Office.Interop.Excel Reference Cannot be found
body: <p>I am having troubles adding the excel reference to my project. I have already installed Primary Interop Assemblies.</p>
  
  <p>The project is detecting the Microsoft.Office.Interop.Word assembly reference correctly but the excel reference still cannot be found.</p>
  
  <p>When I try to manually add the reference, I right click the project, add reference, navigate to the Microsoft.Office.Interop.Excel file and try to add it manually. Once i select the reference I then make sure the reference is checked, then hit ok. Nothing happens, it fails to actually add the reference path to the project. </p>
  
  <p>Using VS2012 Ultimate.</p>
  
  <p>Any suggestions on what I can do to get the project to see the excel reference?</p>