Roaming Network with Extreme and Express

I assume that the AirPort Extreme is operating normally if the AirPort Express devices are not powered up.

You are missing an important step in the setup of each AirPort Express. Please follow the instructions that I have provided below carefully.

Connect an Ethernet cable from one of the three LAN <--> ports on the AirPort Extreme to the WAN "O" port on the AirPort Express. I assume that you have tested the Ethernet cable to make sure that it is working correctly.

Power up the Express and let it run a minute or two

Hold in the reset button on the Express for 7-8 seconds and release

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

Now run the setup "wizard". The first screen to appear will look similar to what you see below, except that you will see your devices pictured and network name displayed.

Type in a device name that you want to call the AirPort Express......something like DenExpress.....for example.

Click Next

Now watch the next screen very carefully to verify that the AirPort Express is being set up to "extend using Ethernet". This will confirm that the setup wizard has picked up the wired Ethernet cable connection and it will apply the correct settings automatically for the Express to work in an "extend using Ethernet" or "roaming" configuration.

When you see the message of Setup Complete, click Done, and you are done. Set up the second Express exactly the same way, except give it a different device name.

I think by now you can see where things were going wrong before. You were setting up each Express to extend using wireless, so the Express was expecting a wireless connection from the AirPort Extreme. Then, when you connected Ethernet to the Express, this created a huge feedback loop that effectively crashed the network.

Bottom line.....the wizard will set up things automatically and correctly based on what it "sees". If it does not "see" an Ethernet connection between the AirPorts, then the new AirPort will be set up to extend using only wireless.

If you want to set up the Express in a roaming network......with Ethernet connections between the AirPorts.....you must establish that wired connection......before.....you run the setup wizard. Then, despite what you might think, the Express will actually be set up to create a wireless network that uses the same wireless network name and password as the main network. This is a roaming network.

Make sense?

Had to set up each express to extend wireless network (no ethernet connected to any device at this point) because that is the only option in Airport Utility wizard. Then change the wireless settings to “Create Wireless Network,” on the Expresses one at a time and use same network name and password.

No, you didn't. Please read my post above to learn that you were leaving out a very important step in the process.

If you don't have an Ethernet connection to the Express when you run the setup, the wizard will assume that is the way that you want to set up the Express........using wireless, not Ethernet.

If you connect Ethernet before you run the setup, the wizard will set things up correctly for a wired connection.