title: the classes are not accessible under the same name space C# ASP.NET
body: <p>The project is in C# ASP.NET; I have some classes under the same namespace. I put them in a separate folder of the project. The problem is that these classes are not accessible to others in this folder.</p>
  
  <pre><code>namespace MNS
  {
      public class data_api
      {
          public string key { get; set; }
  
          public decimal? value { get; set; }
          public string datetime { get; set; }
      }
  }
  
  namespace MNS
  {
      public class respuestaJson
      {
          public byte estatus { get; set; }
          public string descripcion { get; set; }
          public List&lt;List&lt;data_api&gt;&gt; json_respuesta { get; set; }
      }
  }
  </code></pre>
  
  <p>these two classes are separate files in the same folder, but I have an error in the "respuestaJson" class that is shown: " CS0246 The type or namespace name could not be found (are you missing a using directive or an assembly reference?)"</p>
  
  <p>when I create the same file in the App_Code folder, it is working</p>