wirelessly extended network with Airport Express (2d gen.) / The Router is a Zyxcel

Sorry, but the AirPort Express cannot be configured to "extend a wireless network" with a Zyxel router. The AirPort Express can only extend the network if you have another Apple router providing the wireless signal.

So, the AirPort Express will work OK for AirPlay, since it can "join" virtually any network. But....it can only "extend" an Apple network.

You can, but the Ethernet cable must be permanently connected at all times.

Post back if you need some help with the setup. A tip would be that you must have the AirPort connected via Ethernet before you set it up.

We would need to know what operating system you are using on the device that will be used to set up the AirPort Express.

Power up the Express and then hold in the reset button on the back of the device for 7-8 seconds and release. Allow a full minute for the Express to restart.

Connect an Ehernet cable from a LAN <--> port on the Zyxel modem/router to the WAN "O" port on the Express

Click the WiFi icon at the top of the Mac's screen. Click on AirPort Express

The next screen will look like this, except that you will see a picture of your Express version:

Network Name...............Type in the name of the Zyxel wireless

Base Station Name........Type in a name that you want to call the Express

Password.......................Type in the password for the Zyxel wireless

Verify..............................Type in the password to confirm

Click Next

That should be it. Wait for a message of Setup Complete, then click Done.