PageRequestManagerParserErrorException when changing Response during AJAX request

Question

I get an exception after clicking on a button or performing somekind of ajax operation inside AjaxPanel.

SCRIPT5022: Sys.WebForms.PageRequestManagerParserErrorException: The message received from the server could not be parsed. Common causes for this error are when the response is modified by calls to Response.Write(), response filters, HttpModules, or server trace is enabled. Details: Error parsing near '

< !DOCTYPE html>. Telerik.Web.UI.WebResource.axd, line 15 character 16238

On ASP.NET 4.0 with Telerik. This happens only on IE10. Meaning - works perfectly on chrome, Mozilla, previous IE.

I applied the hotfixes KB2600088 and KB2783767 on the server but still nothing. This is Windows Server 2003 Standard Edition 32-bit.

What can I do?

Answer 1

clicking on a button or

What can I do?

If you are modifying the HttpResponse state, it is necessary to move this "button" from the Telerik AjaxPanel/MS UpdatePanel.

See the Sys.WebForms.PageRequestManagerParserErrorException - what it is and how to avoid it blog post for more information.