Never update firmware over Wi-Fi. A sudden signal drop can "brick" your router. Use an Ethernet cable to connect your PC directly to the router's LAN port.
Login with the default credentials: for both username and password. Tenda D301 Firmware Update
Updating the firmware of your Tenda D301 N300 Wireless ADSL2+ Modem Router Go to product viewer dialog for this item. Never update firmware over Wi-Fi
Before starting the update process, follow these critical safety measures to prevent permanent damage to your device: Tenda D301 Firmware Update