@ManjunathGowda The negotiation speed setting is only for the Internet port (WAN port). This issue usually comes from bad ethernet cable crimping/connectors or faulty ethernet ports. Try using...

@Fabien31 RE700X doesn't support an etehernet backhaul, only wireless - that's the reason for your issue. The only RE which supports an ethernet backhaul for now is RE315.

@mahajan Set your Archer C6 in AP mode - details (Case 1). Configure its LAN IP address with a static IP 192.168.1.254 and disable its DHCP server. This should work for you and will extend your...

@AlanHockey You can do a ping test with your laptop when it is connected either with your main router or with the RE. If the RE is with an IP address 192.168.0.254 start a ping to see if you have...

@Messi9CR07 You can contact your local support for further assistance on your issue.

@Dirk68 When doing a backup the local admin password would be backed up too. So your only option is to using the TP-Link ID login if you don't want to reset the device.