title: PIA's Installed but still receiving interop error
body: <p>I am trying to use the Microsoft.Office.Interop.xxxxxxx namespace but Visual Studio 2010 is not providing an option for "interop". I have the PIA's installed for office12 and office14, I have included them in the 'References' in the Solution Explorer, but it is not working. </p>
  
  <p>The code I am trying to call the namespace with is:</p>
  
  <pre><code>    using Excel = Microsoft.Office...;
  </code></pre>
  
  <p>After "Office.", I am only given the option for "Core". So it would look like this</p>
  
  <pre><code>    using Excel = Microsoft.Office.Core;
  </code></pre>
  
  <p>This matches the reference that was imported...but using this namespace does not seem to be useful. </p>
  
  <p>My question is how do I get the Microsoft.Office.Interop option to be accepted and display in intellisense?</p>
  
  <p>Example:</p>
  
  <pre><code>    using Excel = Microsoft.Office.Interop.Excel;
  </code></pre>
  
  <p>Error message being received for 'Interop'= 
  "The type or namespace name 'Interop' does not exist in the namespace 'Microsoft.Office' (are you missing an assembly reference?)</p>
  
  <p>The assembly that I loaded in the Solution Explorer is "Microsoft Office 14.0 Object Library" TypeLib Version 2.5. The assembly path = "C:\Program Files\Common Files\Microsoft Shared\OFFICE14\MSO.DLL</p>
  
  <p>Thanks for any suggestions!</p>