Server Error in '/' Application.

Sequence contains no elements

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 no elements

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:


[InvalidOperationException: Sequence contains no elements]
   System.Linq.Enumerable.First(IEnumerable`1 source) +264
   Umbraco.Core.Configuration.UmbracoSettings.ContentErrorsElement.get_Error404Collection() +85
   Umbraco.Core.Configuration.UmbracoSettings.ContentElement.get_Error404Collection() +17
   Umbraco.Web.Routing.ContentFinderByLegacy404.TryFindContent(PublishedContentRequest pcr) +492
   Umbraco.Web.Routing.ContentLastChanceFinderByNotFoundHandlers.HandlePageNotFound(PublishedContentRequest docRequest) +473
   Umbraco.Web.Routing.ContentLastChanceFinderByNotFoundHandlers.TryFindContent(PublishedContentRequest docRequest) +10
   Umbraco.Web.Routing.PublishedContentRequestEngine.HandlePublishedContent() +529
   Umbraco.Web.Routing.PublishedContentRequestEngine.FindPublishedContentAndTemplate() +251
   Umbraco.Web.Routing.PublishedContentRequestEngine.PrepareRequest() +107
   Umbraco.Web.UmbracoModule.ProcessRequest(HttpContextBase httpContext) +379
   Umbraco.Web.UmbracoModule.<Init>b__8(Object sender, EventArgs e) +80
   System.Web.SyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +141
   System.Web.HttpApplication.ExecuteStepImpl(IExecutionStep step) +48
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +71


Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.7.4087.0