When calling a web service using ASP.NET AJAX, if an error occurs the error information may exclude any error details and just provide the following:

Stack Trace: <empty>
Error: There was an error processing the request.
Status Code: 500
Exception Type: <empty>
Timed Out: false

This occurs when the web.config file customErrors element's mode attribute is set to "On" or "RemoteOnly" and you are not on the server.

To get the full detailed error information, ensure the mode attribute is set to "On", or "RemoteOnly" if accessing from a remote machine.