$Ajax POST not working under virtual web site in IIS 7.5

$Ajax POST not working under virtual web site in IIS 7.5

In the code below, when hosted in IIS 7.5 in a Virtual Web site on the web server, the $ajax POST won't work unless the alert("Records Saved Sucessfully"); is there. If I leave that out only a GET is submitted and the page refreshes.  On my DEV box it works fine without the alert.  A POST is submitted if the alert is there. Another type of function won't work (like a function that adds numbers, or does nothing).
This seems to me like a jquery bug.
 
if (maxchk < 2) {

// var urlvar = actionType == 'save' ? '/DeDupList/SubmitChecks' : '/DeDupList/SubmitHold';

var urlvar;

if (actionType == 'save' ) {

urlvar = ' @Url.Action( "SubmitChecks" , "DeDupList" ) ' ;

}

else {

urlvar = ' @Url.Action( "SubmitHold" , "DeDupList" ) ' ;

};

$.ajax({

url: urlvar,

type: 'POST' ,

processData: false ,

dataType: 'text' ,

data: JSON.stringify({ payload: payload }),

contentType: "application/json; charset=utf-8" ,

success: function (data) {

rresult = data;},

error: function (xhr, ajaxOptions, thrownError) {

rresult= "Error Saving:" + thrownError.error ;

alert(rresult);

}

});

alert( "Records Saved Successfully" ); // This alert is necessary or else the POST does not happen. 

}

else {

alert( "please choose only one match per lab report" );

}