I'm sure there is a Microsoft exam on how to handle custom errors in ASP.NET, and even how to verify query strings before processing them. It might be in their forums, http://forums.microsoft.com, but not at this URL, http://forums.microsoft.com... Yep, we have a Server Error in '/Communities' Application in full display with instructions on how to turn on custom error handling. Obviously no web application I've every written would do something ......