System.NullReferenceException: Object reference not set to an instance of an object.
   at ASP.SPWI.TreeHelpers.<>c__DisplayClass0_0.<RenderSingleCourse>b__0(TextWriter __razor_helper_writer)
   at System.Web.WebPages.HelperResult.WriteTo(TextWriter writer)
   at System.Web.WebPages.WebPageBase.Write(HelperResult result)
   at CallSite.Target(Closure , CallSite , _Page_Views_MacroPartials_Speedware_SPWI_UVT_With_Filter_cshtml , Object )
   at ASP._Page_Views_MacroPartials_Speedware_SPWI_UVT_With_Filter_cshtml.Execute() in d:\web\localuser\kulturskolentro.no\public_html\Views\MacroPartials\Speedware\SPWI_UVT_With_Filter.cshtml:line 109
   at System.Web.WebPages.WebPageBase.ExecutePageHierarchy()
   at System.Web.Mvc.WebViewPage.ExecutePageHierarchy()
   at System.Web.WebPages.WebPageBase.ExecutePageHierarchy(WebPageContext pageContext, TextWriter writer, WebPageRenderingBase startPage)
   at System.Web.Mvc.RazorView.RenderView(ViewContext viewContext, TextWriter writer, Object instance)
   at System.Web.Mvc.BuildManagerCompiledView.Render(ViewContext viewContext, TextWriter writer)
   at Umbraco.Core.Profiling.ProfilingView.Render(ViewContext viewContext, TextWriter writer)
   at Umbraco.Web.Mvc.ControllerExtensions.RenderViewResultAsString(ControllerBase controller, ViewResultBase viewResult)
   at Umbraco.Web.Macros.PartialViewMacroEngine.Execute(MacroModel macro, IPublishedContent content)
   at Umbraco.Web.Macros.PartialViewMacroEngine.Execute(MacroModel macro, INode node)
   at umbraco.macro.LoadPartialViewMacro(MacroModel macro)
   at umbraco.macro.renderMacro(Hashtable pageElements, Int32 pageId)
   at Umbraco.Web.UmbracoComponentRenderer.RenderMacro(macro m, IDictionary`2 parameters, page umbracoPage)
   at Umbraco.Web.UmbracoComponentRenderer.RenderMacro(String alias, IDictionary`2 parameters, page umbracoPage)
   at Umbraco.Web.UmbracoComponentRenderer.RenderMacro(String alias, IDictionary`2 parameters)
   at Umbraco.Web.UmbracoHelper.RenderMacro(String alias, IDictionary`2 parameters)
   at ASP._Page_Views_Partials_grid_editors_Macro_cshtml.Execute() in d:\web\localuser\kulturskolentro.no\public_html\Views\Partials\grid\editors\Macro.cshtml:line 15
   at System.Web.WebPages.WebPageBase.ExecutePageHierarchy()
   at System.Web.Mvc.WebViewPage.ExecutePageHierarchy()
   at System.Web.WebPages.WebPageBase.ExecutePageHierarchy(WebPageContext pageContext, TextWriter writer, WebPageRenderingBase startPage)
   at System.Web.Mvc.RazorView.RenderView(ViewContext viewContext, TextWriter writer, Object instance)
   at System.Web.Mvc.BuildManagerCompiledView.Render(ViewContext viewContext, TextWriter writer)
   at Umbraco.Core.Profiling.ProfilingView.Render(ViewContext viewContext, TextWriter writer)
   at System.Web.Mvc.HtmlHelper.RenderPartialInternal(String partialViewName, ViewDataDictionary viewData, Object model, TextWriter writer, ViewEngineCollection viewEngineCollection)
   at System.Web.Mvc.Html.PartialExtensions.Partial(HtmlHelper htmlHelper, String partialViewName, Object model, ViewDataDictionary viewData)
   at System.Web.Mvc.Html.PartialExtensions.Partial(HtmlHelper htmlHelper, String partialViewName, Object model)
   at ASP._Page_Views_Partials_grid_editors_Base_cshtml.Execute() in d:\web\localuser\kulturskolentro.no\public_html\Views\Partials\grid\editors\Base.cshtml:line 20