i am getting 2,500 type 500 url errors in google webmaster tools. These pages are faceted navigation results that can not be reached by a site visitor. These pages do not exist. We are using faceted navigation with the Volusion platform (asp.net, I think). I have specified url parameters in webmaster tools so that google will not try to index anything faceted. This does not stop the errors from generating. I am concerned about how this might effect seo (bleeding page rank). I can provide additional information if needed. I am not sure how to solve this. I have started down the path of creating 301's, but having some difficulty there as well.