Server Error in '/' Application.

Sequence contains more than one matching element

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.InvalidOperationException: Sequence contains more than one matching element

Source Error:


Line 16:     
Line 17:     // try to find menu item
Line 18:     MenuItem menuitem = nav.AllMainMenu.SingleOrDefault(i => i.Key == keys.Last());
Line 19:     
Line 20:     // found menu item by last key

Source File: c:\Web\mcms3\Cms_Data\Sites\VesnaSposaV2\Templates\Layouts\404-handeler\template.cshtml    Line: 18

Stack Trace:


[InvalidOperationException: Sequence contains more than one matching element]
   System.Linq.Enumerable.SingleOrDefault(IEnumerable`1 source, Func`2 predicate) +352
   ASP._Page_Cms_Data_Sites_VesnaSposaV2_Templates_Layouts_404_handeler_template_cshtml.Execute() in c:\Web\mcms3\Cms_Data\Sites\VesnaSposaV2\Templates\Layouts\404-handeler\template.cshtml:18
   System.Web.WebPages.WebPageBase.ExecutePageHierarchy() +252
   System.Web.Mvc.WebViewPage.ExecutePageHierarchy() +123
   System.Web.WebPages.WebPageBase.ExecutePageHierarchy(WebPageContext pageContext, TextWriter writer, WebPageRenderingBase startPage) +122
   System.Web.Mvc.ViewResultBase.ExecuteResult(ControllerContext context) +378
   System.Web.Mvc.<>c__DisplayClass1c.<InvokeActionResultWithFilters>b__19() +31
   System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilter(IResultFilter filter, ResultExecutingContext preContext, Func`1 continuation) +448
   System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilter(IResultFilter filter, ResultExecutingContext preContext, Func`1 continuation) +448
   System.Web.Mvc.ControllerActionInvoker.InvokeAction(ControllerContext controllerContext, String actionName) +659
   System.Web.Mvc.Controller.ExecuteCore() +146
   System.Web.Mvc.ControllerBase.Execute(RequestContext requestContext) +91
   System.Web.Mvc.<>c__DisplayClassb.<BeginProcessRequest>b__5() +60
   System.Web.Mvc.Async.<>c__DisplayClass1.<MakeVoidDelegate>b__0() +25
   System.Web.Mvc.<>c__DisplayClasse.<EndProcessRequest>b__d() +60
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +431
   System.Web.HttpApplication.ExecuteStepImpl(IExecutionStep step) +75
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +158


Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.8.4494.0