Server Error in '/app' Application.

Sequence contains no 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 no matching element

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 matching element]
   System.Linq.Enumerable.First(IEnumerable`1 source, Func`2 predicate) +381
   BentleyIT.LearnWeb.Controllers.PublicController.BrowseLearningPaths(String productlineId, String productId, String generationId, String languageId, String courseLevelId, String LPStatusId, String CMStatusId, Boolean CustomLP, String searchKey, String resultType, Boolean searchByLearningpath) in d:\Builds\12\EngagementPlatform\App_BentleyIT.LearnWeb\Sources\Source\Apps\Learn\LearnWeb\BentleyIT.LearnWeb.Registration\Controllers\PublicController.cs:852
   lambda_method(Closure , ControllerBase , Object[] ) +848
   System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters) +280
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters) +35
   System.Web.Mvc.<>c__DisplayClass15.<InvokeActionMethodWithFilters>b__12() +80
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func`1 continuation) +454
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func`1 continuation) +454
   System.Web.Mvc.ControllerActionInvoker.InvokeAction(ControllerContext controllerContext, String actionName) +658
   System.Web.Mvc.Controller.ExecuteCore() +143
   System.Web.Mvc.ControllerBase.Execute(RequestContext requestContext) +91
   System.Web.Mvc.<>c__DisplayClassb.<BeginProcessRequest>b__5() +57
   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() +602
   System.Web.HttpApplication.ExecuteStepImpl(IExecutionStep step) +195
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +128


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