event is null or not an object

[sejal17]

hello all,
i am developing asp.net application that is running on local machine but when i am uploading this application on web server it is display error when i am clicking on edit/delete in grid.

it display error like this

"event is null or not an object"

when i am checking this error in mozila it display error in WebUiValidtion. js file

in
function ValidatorCommon OnSubmit() {
var result = !Page_BlockSubm it;
Page_BlockSubmi t = false;
event.returnVal ue = result;
return result;
}

if any one have solution then help me..

Thanks in Advance..