I converted an ASP.NET 3.5 web site into ASP.NET 4.0 and have run into some problems. When I don't put <location path="Telerik.Web.UI.WebResource.axd"> in the web.config, the Membership Provider works and I get the Microsoft JScript runtime error: 'Telerik' is undefined error. When I put <location path="Telerik.Web.UI.WebResource.axd"> in the web.config, the I don't get the Telerik error, but the Membership Provider no longer works.