Hi all, I have developed Silverlight application using RiaServices.I have implemented Forms Authentication which works fine on local server but when i host my application to a Winhost RiaContext.Current.Authentication.User returns null. I am not able to evaluate what is happening.I have used fiddler to track the request and got following error; /ClientBin/DataService.axd/NX27KAPP-Web-NX27KDomainService/Login--- Http 400 .Resources not found. Any help would be appreciated.