InnerMessage:Object reference not set to an instance of an object.

InnerStackTrace:

   at DotNetNuke.Authentication.Facebook.Login.AddCustomProperties(NameValueCollection properties)
   at DotNetNuke.Services.Authentication.OAuth.OAuthClientBase.AuthenticateUser(UserData user, PortalSettings settings, String IPAddress, Action`1 addCustomProperties, Action`1 onAuthenticated)
   at DotNetNuke.Services.Authentication.OAuth.OAuthLoginBase.OnLoad(EventArgs e)
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)