Error: Sys. WebForms.
When trying to run a .NET web-application which uses Ajax either:
This error (or behaviour) is caused by the interaction between Ajax and
the WebServer when the WebServer generates an error and thus the response
by an error in the underlying VB.NET or C#, but is being masked because
of the use of Ajax.
Attempt to reproduce the problem while debugging in the Visual Studio
environment. The underlying error will then become apparent, allowing you
to address it.
These notes have been tested within Microsoft Visual Studio
.NET 2008 running under Windows Vista, and may apply to other versions as
About the author: Brian Cryer
is a dedicated software developer and webmaster. For his day job he
develops websites and desktop applications as well as providing
IT services. He moonlights as a technical author and consultant.