Ajax Problem

[eluser]Unknown[/eluser]
Hi

I am making the following Ajax request :

xmlhttp.open("GET",'<?php echo base_url();?>ajax_handler/get_tax_for_order_form/2',true);

which is returning no responses when ONLINE, but on a local server, this is working perfectly.

In IE, the browser console says "Access Denied", Firebug shows the request as RED marked.

I can not figure out the problem as same code is running locally very well.

Help needed. Thanks.