Ensure you have the correct firmware for your specific hardware version (R6300v1 vs. R6300v2) from the Netgear Support Download Center .
Connect your PC directly to one of the router’s LAN ports using an Ethernet cable. Netgear R6300 Firmware Recovery Utility
This is the most reliable way to force-load firmware when the web GUI is down. Ensure you have the correct firmware for your
Keep holding reset and the power for another 30 seconds . Netgear R6300 Firmware Recovery Utility