title: MVC4 validation summary not showing
body: <p>Have created a model and with required fields and used to create a form like so:</p>
  
  <p>Model:</p>
  
  <pre><code>public class formModel {
      [Required]
      public string name {get;set;}
      [Required]
      public string Add1 {get;set;}
      etc....
  }
  </code></pre>
  
  <p>View:</p>
  
  <pre><code>@model myProj.Models.formModel
  
  @using (BeginForm("Action", "Controller", FormMethod.Post))
  {
      @Html.TextBoxFor(f =&gt; f.name)
      @Html.TextBoxFor(f =&gt; f.Add1)
      etc...
  
      @Html.ValidationSummary()
      &lt;button type="submit" value="submit"&gt;Submit&lt;/button&gt;
  }
  </code></pre>
  
  <p>Controller:</p>
  
  <pre><code>[HttpPost]
  public ActionResult Action(formModel f)
  {
      if (ModelState.IsValid)
      {
          // Do Stuff here
          return RedirectToAction("Result");
      }
      return RedirectToAction("Form", new { id = "showForm" });
   }
  </code></pre>
  
  <p>Problem is the validation summary is being displayed if the model is in valid. Have used same approach on lots of other forms and has been fine.</p>
  
  <p>Any ideas?</p>