Adding Multiple Airport Extreme to a wired ethernet network

I would recommend that you temporarily move the second AirPort Extreme close to the first AirPort Extreme for the setup, if possible.

Connect a short spare Ethernet cable......any length will do......from one of the 3 LAN <--> Ethernet ports on the back of the first AirPort to the WAN "O" port on the second AirPort

Power up the second AirPort if it is not already on, then hold in the reset button on the back of the second AirPort for 7-8 seconds and release

Allow a full minute for the second AirPort to restart to a slow blinking amber light status

On your Mac......

Click on the WiFi menu at the top of the screen

Look for a listing of New AirPort Base Station

Click directly on AirPort Extreme

When you click on AirPort Extreme, that will start up the AirPort Utility setup "wizard". The wizard will take a few seconds to analyze the network and then display a screen that looks like the example below except that you will see your devices and network name appear.

Type in a device name that you want to call the second AirPort Extreme

Click Next

Watch the next screen that appears very carefully to see the AirPort Extreme is being set up to extend using Ethernet. This will confirm that the setup wizard has picked up the Ethernet connection between the two AirPorts and apply the correct settings to the second AirPort.

When you see the message of Setup Complete, click Done......and the second AirPort is now configured correctly.

Power off the second AirPort.

Move the second AirPort back to the location where it is needed, connect the Ethernet cable to the WAN "O" port on the AirPOrt and power up the AirPort.

If your Ethernet wiring is working correctly, then so too will the second AirPort Extreme be operating correctly.

If you cannot temporarily move the second AirPort close the first AirPort for the setup that I have outlined above, you can go ahead and connect it to the Ethernet cable at the remote location. Unfortunately, if there are any issues, we won't know whether the AirPort is at fault or your Ethernet wiring may have a problem. That's why I always recommend connecting AirPorts directly together for setups.

Please post back on your results.

It sounds like you might have configured the second Airport Extreme to "Extend a wireless network", in which case the second AirPort Extreme will try to connect to the first using a Wi-Fi connection.......not using an Ethernet connection.

Another way to say the same thing is that the "Extend a wireless network" setting is used only when the second AirPort will connect to the first using a wireless connection. It is not the correct setting to use when the AirPort connects to the network using an Ethernet connection.

In addition, if you have configured the second Extreme to "Extend a wireless network" and have also connected an network Ethernet cable to the second Extreme, this will will create a huge feedback loop and effectively crash the network near the second AirPort. WiFi devices will not be able to connect to the second AirPort and instead will try to connect to the first AirPort.

If this sounds like it might be your issue, the solution is to start over and reconfigure the second Extreme using the AirPort Utility setup "wizard" to "extend using Ethernet". We can provide the simple steps if you can let us know whether you are using a Mac or an iPhone / iPad for the setup.

Great, not sure why you marked your "thanks" as the solution to your issue, but glad that you have things working well.