function onRequestStart_CheckDownload(sender, args) {
    // GRID EXPORTING
    if (args.get_eventTarget().indexOf("ExportToExcelButton") >= 0 ||
                    args.get_eventTarget().indexOf("ExportToWordButton") >= 0 ||
                    args.get_eventTarget().indexOf("ExportToCsvButton") >= 0 ||
                    args.get_eventTarget().indexOf("ExportToPdfButton") >= 0) {
        args.set_enableAjax(false);
    }
    // BUTTONS STARTED WITH 'btnDownload'
    if (args.get_eventTarget().indexOf("btnDownload") >= 0) {
        args.set_enableAjax(false);
    }
    // BUTTONS STARTED WITH 'btnGenerate'
    if (args.get_eventTarget().indexOf("btnGenerate") >= 0) {
        args.set_enableAjax(false);
    }
}