The process of downloading the ASUS RT-AC66U Router Firmware 3.0.0.4.378.4850 Beta driver should begin automatically after a few seconds. If this does not occur, click on one of the links below (we recommend downloading the ASUS RT-AC66U Router Firmware 3.0.0.4.378.4850 Beta driver from the primary server - this is the manufacturer’s ASUS official website). If the download still fails to run, check whether your anti-virus software is not blocking the connection to the manufacturer server of the ASUS RT-AC66U Router Firmware 3.0.0.4.378.4850 Beta diver.