PHP ajax no works in explorer 11 [win7]( 11.0.9600.17843 and 11.0.9600.19155 )

Dear support :

Same code ( ajax post func ) run on [win10] (11.1112.15063.0), Firefox 56.0 & 63.0 ; Chrome  61.0.3163.100 & 70.0.3538.77 work fine.

But in [win7] ( 11.0.9600.19155 ) got 500 Internal error.

Try modify X-UA-Compatible content ( IE=edge or IE=10 .. ) and update jquery-1.9.1.js to 1.12.1 but nowork ....

    Any ideas ? please give me advise. thanks a lot.

      ps : lighttpd/1.4.45 + linux 3.14 : code base on RDK Central Reference Design Kit ccsp-webui.

sample code as below :
-------------------------------------------
<script type="text/javascript">
$(document).ready(function() {
....
$.ajax({
    type:"POST",
    url:"actionHandler/ajax_hs_port_forwarding.php",
    data:{del:delVal},
    success:function(){
        jHide();
        window.location.reload();
    },
    error:function(){
        jHide();
        jAlert("Error! Please try later!");
    }
});