UPDATE: March 7th, 2014 - The approach in this video is not needed anymore. Please read this post to learn why: "Three simple ways to handle DevExpress ASP.NET Callback Errors"
Check out this 6 minute video that shows you how to handle those pesky Ajax callback errors. If you’ve ever experienced one of these then you know how frustrating they are. The usual cause is a server error that occurs during a callback and fails to notify the client side. Now you can handle these errors with elegance by just enabling the ASPxHttpHandler module within your ASP.NET website or project. This module sits within the ASP.NET Request pipeline and is able to track the control that initiated the callback as well as subsequent errors. The module also allows you to either report back to the control or redirect to a general error page.
Click the image below to see this video on the brand new DevExpress Channel: