[Solved] Infamouse Error 500 on Grid - No Circular References here

[Forest]

Hi all,

Whenever I try to do a page, refresh, sort, etc, anything with Ajax, I get Error 500.  I sniffed it out in Fiddler and noticed the error was this:

The view 'GetGridModel' or its master was not found or no view engine supports the searched locations. The following locations were searched:   etc, etc.... 

Here's the controller: 

public class FrontDeskController : Controller
   {
       private readonly IRepository _repository;

       public FrontDeskController(IRepository repository)
       {
           _repository = repository;
       }

       public ActionResult Index()
       {
           return View();
       }

       [OutputCache(Duration = 0)]
       public ActionResult Search(VisitorSearchViewModel model)
       {
           return DisplayVisitorSearchResults(model);
       }

       private ActionResult DisplayVisitorSearchResults(VisitorSearchViewModel model)
       {
           var response = GetVisitorSearchResponse(model);

           if (response.Success)
           {
               var visitorModels = response.List.ConvertToVisitorViewModelList();

               StoreVisitorInformationInSession(model, visitorModels);
               return PartialView("_Visitors", visitorModels);
           }
           return DisplayErrorView(response);
       }

       private ActionResult DisplayErrorView(ResponseBase response)
       {
           return Json(new
                           {
                               Success = "false",
                               Title   = "Error Retrieving Visitors.",
                               Message = response.Message
                           });
       }

       private ListResponseBase<Visitor> GetVisitorSearchResponse(VisitorSearchViewModel model)
       {
           var visitorQuery = new VisitorSearchQuery(_repository);

           return visitorQuery.Where(model)
                              .PageOfResults(1, int.MaxValue);
       }

       private void StoreVisitorInformationInSession(VisitorSearchViewModel model, IEnumerable<VisitorViewModel> visitorModels)
       {
           Session["LastFourSSN"] = model.LastFourSSN;
           Session["LastName"]    = model.LastName;
           Session["List"]        = visitorModels.ToList();
       }

       [GridAction]
       public ActionResult GetGridModel()
       {
           return View(new GridModel((List<VisitorViewModel>)Session["List"]));
       }
   }

And here's the partial view: 

@model IEnumerable<CraftTraxNG.Model.ViewModels.VisitorViewModel>

@(Html.Telerik().Grid(Model)
    .Name("Visitors")
    .DataKeys(dataKeys => dataKeys.Add(o => o.Id))
    .Columns
        (columns =>
        {
            columns.Bound(o => o.LastFourSSN).Width(50).Filterable(false).Title("SSN");

            columns.Bound(o => o.FirstName).Width(100).Filterable(true).Title("First");

            columns.Bound(o => o.Middle).Width(50).Filterable(false).Title("Middle");
            columns.Bound(o => o.LastName).Width(150).Filterable(false).Title("Last");
            columns.Bound(o => o.FormattedPhoneNumber).Width(125).Filterable(true).Title("Primary Phone");
            columns.Bound(o => o.FormattedSecondaryPhoneNumber).Width(125).Filterable(true).Title("Secondary Phone");
            columns.Bound(o => o.VisitorStatusDisplay).Width(100).Filterable(false).Title("Status");

            columns.Bound(o => o.ActionsUrl)
                   .Encoded(false)
                   .ClientTemplate("<#= ActionsUrl #>")
                   .Title("Actions");
        })

        .DataBinding(dataBinding => dataBinding.Ajax()
                                               .Select("GetGridModel", "FrontDesk")
                                               .Enabled(true))

    .NoRecordsTemplate("No records found")
    .Scrollable(scrolling => scrolling.Enabled(false))
    .Sortable(sorting => sorting.Enabled(true))
    .Pageable(paging => paging.Enabled(true))
    .Filterable(filtering => filtering.Filters(filters => filters.Add(o => o.FirstName).StartsWith("")))
    .Groupable(grouping => grouping.Enabled(false))
    .Footer(true)
)

<p>
    @Html.ActionLink("Create New Visitor", "Create", "Visitor", new { area = "" }, null)
</p>

Upon the first search, all of the correct data is present.  

When I do a sort or refresh, I have verified the method GetGridModel gets called and in fact the data is still sessioned.  But the call to
the statement "return View(new GridModel((List<VisitorViewModel>)Session["List"]));" sends out the 500 error in a JavaScript alert box. 

For reference, the following script references are on the page: 

<script src="http://ajax.aspnetcdn.com/ajax/jQuery/jquery-1.6.4.min.js" type="text/javascript"></script>
 <script src="http://ajax.aspnetcdn.com/ajax/jquery.validate/1.9/jquery.validate.min.js" type="text/javascript"></script><script src="http://ajax.aspnetcdn.com/ajax/mvc/3.0/jquery.validate.unobtrusive.min.js" type="text/javascript"></script>
 <script src="http://ajax.aspnetcdn.com/ajax/mvc/3.0/jquery.unobtrusive-ajax.min.js" type="text/javascript"></script>
 <script src="http://ajax.aspnetcdn.com/ajax/jquery.ui/1.8.13/jquery-ui.min.js" type="text/javascript"></script>
<script type="text/javascript" src="/Scripts/2011.3.1115/telerik.common.min.js"></script>
<script type="text/javascript" src="/Scripts/2011.3.1115/telerik.grid.min.js"></script>
<script type="text/javascript" src="/Scripts/2011.3.1115/telerik.grid.filtering.min.js"></script>
<script type="text/javascript" src="/Scripts/2011.3.1115/telerik.menu.min.js"></script>

Additionally, a Telerik MVC Menu is present on the layout page. 

Other info: 

.NET Framework - 4.0
MVC 3 Razor view engine
Windows Auth - allow all.
Post variables from Fiddler: 

page=1&size=10&orderBy=LastFourSSN-asc&filter=FirstName~startswith~''

 Any help is much appreciated. 

[Ryan]

Curious about this too, wonder why no response yet?  I'm getting 500 status code alerts from telerik when there are modelstate errors in the process of databinding (this is a search form with required fields).