Open Excel On Server, Run Macro

I'm trying to do something I thought would be simple but seems not to be. I want to open and excel file on the server, run a macro in the excel file and close it.

<%@ Page Language="C#" Debug="true" %>
<%@ Import Namespace="System" %>
<%@ Import Namespace="System.Data" %> 

<html>
 <head>
  <script runat="server">
   void Page_Load(Object s, EventArgs e)
   {
    Excel.Application MSExcel = new Excel.Application();
    MSExcel.Quit();
   }
  </script>
  </head>
  <body>
  <asp:Label ID="lblMsg" runat="server" />
 </body>
</html>

When I run that code I get this error: "The type or namespa ...