I have a client web application to capture an order. I have set web reference to ipx.asmx on my local machine. I can access web methods on my form.aspx.cs through .NET intellesence. Everything looks fine. No build errors. But when I run my app. I get error on method ws.DoItUsernamePwd(AuthenticationEMail, AuthenticationPassword, sw.ToString()). WSI is set up fine because same method I'm able to run when I open ipx.asmx in firefox. There the same method works fine. Please help. I'm sure it is something really small. But don't know what is it.