c# - The Select Method must return one of "IQueryable" or "IEnumerable" -

After

After I upgrade to Microsoft Owin Authentication / OpenAuth2 from Dotnet.OpenAuth, when I try to access the login page that I This error is detected.

The selection method should return one of "IQueryable" or "IEnumerable" or "Microsoft.AspNet.Membership.OpenAuth.ProviderDetails" when the itemtype is set to "Microsoft.AspNet.Membership.OpenAuth .ProviderDetails ".

Visual Studio 2013 ASP.NET C #

What could cause this error?

This is the line that throws an error from OpenAuthProviders.ascx.cs:

  public IEnumerable & lt; String & gt; GetProviderNames () return to {Context.GetOwinContext () select Authentication.GetExternalAuthenticationTypes () (t = & gt; t.AuthenticationType). }  

is OpenAuthProvider.ascx

  <% @ control language = "C #" AutoEventWireup = "true "CodeBehind =" OpenAuthProviders.ascx.cs "Inheritance =" quote.account.openoffprovider "%> & Lt; Fieldet class = "open-end-provider" & gt; & Lt; ASP: ListView runat = "server" id = "providerDetails" itemtype = "Microsoft.AspNet.Membership.OpenAuth.ProviderDetails" SelectMethod = "GetProviderNames" ViewStateMode = "Disabled" & gt; & Lt; ItemTemplate & gt; & Lt; Button type = "submit" category = "social logo button & lt;% #: item. Provider name% & gt;" Name = "provider" value = "& lt;% #: item. Provider name% & gt;" Title = "Sign in using your & lt;% #: item. Provider display name% & gt; Account." & Gt; & Lt;% #: Item.ProviderDisplayName% & gt; & Lt; / Button & gt; & Lt; Br / & gt; & Lt; Br / & gt; & Lt; / ItemTemplate & gt; & Lt; EmptyDataTemplate & gt; & Lt; Div class = "message-info" & gt; & Lt; P & gt; No external authentication services configured & lt; A href = "http://go.microsoft.com/fwlink/?LinkId=252803" & gt; This article & lt; / A & gt; See. For information about setting up this ASP.NET application to support logging through external services. & Lt; / P & gt; & Lt; / Div & gt; & Lt; / EmptyDataTemplate & gt; & Lt; / ASP: ListView & gt; & Lt; / Fieldset & gt;