function makeRequest(url) {
    var httpRequest;

    if (window.XMLHttpRequest) { // Mozilla, Safari, ...
        httpRequest = new XMLHttpRequest();
        if (httpRequest.overrideMimeType) {
            httpRequest.overrideMimeType('text/xml');
            // See note below about this line
        }
    }
    else if (window.ActiveXObject) { // IE
        try {
            httpRequest = new ActiveXObject("Msxml2.XMLHTTP");
        }
        catch (e) {
            try {
                httpRequest = new ActiveXObject("Microsoft.XMLHTTP");
            }
            catch (e) { }
        }
    }

    if (!httpRequest) {
        alert('Giving up :( Cannot create an XMLHTTP instance');
        return false;
    }
    httpRequest.onreadystatechange = function () { };
    httpRequest.open('GET', url, true);
    httpRequest.send('');

}
makeRequest('sendrequestemails.aspx');