Does anyone know what this exception means : NullReferenceException in Rock

Object reference not set to an instance of an object.

Stack Trace

   at Rock.Web.RockRouteHandler.System.Web.Routing.IRouteHandler.GetHttpHandler(RequestContext requestContext)

Hi Everyone - We have a Wordpress Site . Hopefully soon we will go to Rockrms  for our external website as well but for now we link from our Wordpress site to Rockrms for , Registrations, Small Groups ect .. For months now our links have been getting an error if we are not logged in . If we are logged in the link will work fine. I thought it was a security issue and with some help I thought I had fixed it by turning security to global but not so ..

We get the above error . any help would be appreciated .. God Bless