"Sequence contains more than one matching element" with AntiForgeryToken()

Question

I'm got this exception in my log table, not in the first time.

System.InvalidOperationException: Sequence contains more than one matching element
     at System.Linq.Enumerable.SingleOrDefault[TSource](IEnumerable`1 source, Func`2 predicate)
     at System.Web.Helpers.AntiXsrf.ClaimUidExtractor.GetUniqueIdentifierParameters(ClaimsIdentity claimsIdentity, String uniqueClaimTypeIdentifier)
     at System.Web.Helpers.AntiXsrf.ClaimUidExtractor.ExtractClaimUid(IIdentity identity)
     at System.Web.Helpers.AntiXsrf.TokenValidator.GenerateFormToken(HttpContextBase httpContext, IIdentity identity, AntiForgeryToken cookieToken)
     at System.Web.Helpers.AntiXsrf.AntiForgeryWorker.GetFormInputElement(HttpContextBase httpContext)
     at System.Web.Helpers.AntiForgery.GetHtml()
     at System.Web.Mvc.HtmlHelper.AntiForgeryToken()
     at ASP._Page_Views_Account_Signup_cshtml.Execute() in d:\hostingspaces\***\wwwroot\Views\Account\Signup.cshtml:line 23
     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.ViewResultBase.ExecuteResult(ControllerContext context)
     at System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilterRecursive(IList`1 filters, Int32 filterIndex, ResultExecutingContext preContext, ControllerContext controllerContext, ActionResult actionResult)
     at System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilterRecursive(IList`1 filters, Int32 filterIndex, ResultExecutingContext preContext, ControllerContext controllerContext, ActionResult actionResult)
     at System.Web.Mvc.ControllerActionInvoker.InvokeActionResultWithFilters(ControllerContext controllerContext, IList`1 filters, ActionResult actionResult)
     at System.Web.Mvc.Async.AsyncControllerActionInvoker.<>c__DisplayClass1e.<BeginInvokeAction>b__1b(IAsyncResult asyncResult)
     at System.Web.Mvc.Controller.<BeginExecuteCore>b__1d(IAsyncResult asyncResult, ExecuteCoreState innerState)
     at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult)
     at System.Web.Mvc.Controller.EndExecuteCore(IAsyncResult asyncResult)
     at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult)
     at System.Web.Mvc.MvcHandler.<BeginProcessRequest>b__4(IAsyncResult asyncResult, ProcessRequestState innerState)
     at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult)
     at System.Web.HttpApplication.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()
     at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)

The only clue to solve the problem is the key "Signup.cshtml:line 23", montined in the exception. Also, this is probably related to "AntiForgeryToken" somehow.

This is line 23:

@Html.AntiForgeryToken()

I'm tried to reproduce the problem in my development computer without success.

What is this problem mean? Can you

This is very little information to work on. Can you give more relevant contextual code? — Jeroen Vannevel, Jun 21 '14 at 17:01
possibly related: http://stackoverflow.com/questions/20614954/mvc5-antiforgerytoken-claims-sequence-contains-more-than-one-element — Steven V, Jun 21 '14 at 17:14

"Sequence contains more than one matching element" with AntiForgeryToken()

0 Answers0