From: bruce barker on
the page processing of the ajax request is throwing an error. session
timeout can cause this, or any processing error on the page.

ajax pages should almost never through errors, they shoudl have code to
recover from almost all errors.

-- bruce (

Jeremy wrote:
> I am getting an error Sys.WebForms.PageRequestManagerServerErrorException:
> An unknown error occured while processing the request on the server. The
> status code returned from the server was:500.
> It appears that this error occurs after I browse to the specific page and
> leave it for a while, then click on a linkbutton within an update panel.
> Has anyone experienced this behavior?