SqlZen i change the conf to get a detailed error. i got this i'm not sure if thats what u need.

No Web service is found in: AutentificacionWS.asmx.

Description: An unhandled exception when running the current Web request. Check the stack trace for more information about the error and where it originated in the code.

Exception Details: System.InvalidOperationException: .

Source Error:

It has generated an unhandled during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:

[InvalidOperationException: No Web service is found in: Autent.ws.]

System.Web.Script.Services.WebServiceData.GetWebServiceData(HttpContext context, String virtualPath, Boolean failIfNoData, Boolean pageMethods, Boolean inlineScript) +1051

System.Web.Script.Services.WebServiceData.GetWebServiceData(HttpContext context, String virtualPath) +48

System.Web.Script.Services.RestHandler.CreateHandler(HttpContext context) +227

System.Web.Script.Services.RestHandlerFactory.GetHandler(HttpContext context, String requestType, String url, String pathTranslated) +185

System.Web.Script.Services.ScriptHandlerFactory.GetHandler(HttpContext context, String requestType, String url, String pathTranslated) +120

System.Web.MaterializeHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +856

System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +188

Información de versión: Versión de Microsoft .NET Framework:4.0.30319; Versión ASP.NET:4.0.30319.34009