Contact fae@tp-link.com.cn for help.

How about status of powerline lights on both units? Follow the guide here to pair them first. Connect to LAN port of WPA4220 and check if interent works. If not, what's the IP address, default...

In some case, it might be a limitation on ISP end. Did you try to contact your ISP? Any anti-virus software or firewall running?

Your guys upgraded the latest firmware? http://www.tp-link.com/en/download/Archer-VR900_V1.html#Firmware If it won't help, you'd better contact TP-LINK support team here....

After reconfigure it, internet light will be on or flashing and there is WAN IP on its web interface but you still cannot access internet wirelessly, right? Try to ping goolge.com and ping 8.8.8.8 on...

Wi-Fi has no password but interent works indeed? Did you connect to LAN port of W8961ND and try to access 192.168.1.1? Power off and power back on your W8961ND. Try again. If you still cannot login,...