The process of downloading the Cisco SPA921 IP Phone Firmware 5.1.8 driver should begin automatically after a few seconds. If this does not occur, click on one of the links below (we recommend downloading the Cisco SPA921 IP Phone Firmware 5.1.8 driver from the primary server - this is the manufacturer’s Cisco 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 Cisco SPA921 IP Phone Firmware 5.1.8 diver.