Sys.WebForms.PageRequestManagerServerErrorException
Raised by the PageRequestManager class to return an error when the server returns an error to the browser.
Remarks
When an error occurs on the server while the request is being processed, an error response is returned to the browser and a PageRequestManagerServerErrorExceptionobject is created by using the Error.create function. To customize error handling and to display more information about the server error, handle the AsyncPostBackError event and use the AsyncPostBackErrorMessage and AllowCustomErrorsRedirect properties. For an example of how to provide custom error handling during partial-page updates, see Customizing Error Handling for ASP.NET UpdatePanel Controls.