grid not updating after process completes

[Binary]

I have a drop down list inside the radgrid and the button outside the radgrid. Also I have asp.net update panel for making the cursor busy while processing. when I changed the drop down value in less than 2 drop down everything works fine and it update the gradgrid after processing complete.  But when I change the 3 or more dropdown list value, I am getting error message like

 

 Unhandled exception at line 15, column 16485 in http://localhost:85124/Telerik.Web.UI.WebResource.axd?_TSM_HiddenField_=RadScriptManager1_TSM&compress=1&_TSM_CombinedScriptsJavaScript runtime error: ....

Sys.WebForms.PageRequestManagerTimeoutException: The server request timed out.   etc   kind of error message. ​

 

Can you please provide suggestion how can I fixed this issue?

 

Thanks in advance

[Eyup]

Hello Binary,

Could you replace the UpdatePanel with RadAjaxPanel or implement RadAjaxManager settings and let me know whether this will resolve the issue? Please use only the RadAjaxPanel or RadAjaxManager. They should not be implemented simultaneously:
http://www.telerik.com/help/aspnet-ajax/ajax-controls-in-ajaxpanel-and-ajaxsettings.html

If the issue remains, temporarily remove any ajaxification on the page and enable your script debugger (FireBug or F12) to see whether a more descriptive script or server error will arise. And if it does, you can debug the problematic lines of the application to track down the issue and root it out.

Also, please remove RadCompression from your web.config in case it is enabled:
http://www.telerik.com/help/aspnet-ajax/compression.html

Hope this helps.

Regards,
Eyup
Telerik