airport problems

Possibly because you may have a configuration issue with both AirPort base stations.

Is your goal to create an extended Wi-Fi network by configuring a roaming network with your base stations? If so, a common mistake when setting up this type of network is that the extending base station is configure to use the "Extend a wireless network" option instead of the "Create a wireless network" one. Might this be your case?

Likely because you already had the AirPort Express configured to "extend a wireless network" and then you plugged the Ethernet cable in.

When you did this, the Express was expecting a wireless connection....because it had already been set up that way.

When it got an Ethernet connection, this created a massive feedback loop and effectively crashed the network.

So, you have to start over and reset the Express back to factory default settings......then make the Ethernet connection.....then set up the Express again so that it will set up to use the Ethernet connection. The setup "wizard" makes this virtually automatic.....assuming your Mac is running Mountain Lion, Mavericks, Yosemite, or El Capitan.

Or, if you want step-by-step, post back to let us know.

You are using a 5 year old version of AirPort Utility. I'll have to see if can find an older Mac here that is running the 10.6.8 operating system. Will advise in a few hours.

This would be much easier and much faster if you have an iPhone or iPad handy. Is that a possibility?

Check to make sure that the Ethernet cable from the Time Capsule connects to the WAN "O" port on the AirPort Express

On the iPhone home screen, tap Settings, then tap WiFi

Tap on AirPort Express under the setting of Setup New AirPort Base Station

The screen will indicate that the AirPort Express will be set up to extend the Time Capsule network

Tap Next

Wait a minute while the wizard sets up everything for you

Tap Done when you see the message that the Express is extending the network

Looks like you got things working with the iPhone "wizard" setup. Compare that to this setup on your Mac using AirPort Utility:

When the AirPort Express appears in AirPort Utility......click Manual Setup

Click the Base Station tab below the row of icons at the top of the window

Next to Base Station Name.....enter a name that you want to call the AirPort Express

Next to WiFi Base Station Password....enter a password

Next to Verify Password....type in the password again

Check Time settings and set the current Time Zone

Click the Wireless tab below the row of icons

Next to Wireless Mode.....select Create a wireless network

Wireless Network Name.....type in the exact same name as the Time Capsule network

Radio Mode = Automatic

Wireless Security = WPA2 Person

Type in the same Wireless Password that the Time Capsule is using

Type in the password again to Verify

Click the Internet icon

Click the Internet Connection tab

Connect Using = Ethernet

Connection Sharing = Off (Bridge Mode)

Click Update to save the settings