Airport Express invalid IP address
I have an Airport Express that is connected through ethernet to my DSL modem (Zyxel C3000Z). It has been working fine for years. But lately the amber light has been blinking and I lose the Internet connection. I could restart it and it would connect again (green light) for days or weeks. But now it just won't connect. I can still connect my MacBook Pro and iPads to the Airport's WiFi network, but I don't get a connection to the Internet. The DSL modem shows a connection on the ethernet port, so it definitely sees the Airport.
When I use Airport Utility and look at the Airport Express settings, there is an error message saying it does not have a valid IP address. I have tried setting a static IP but I'm not entirely sure I'm doing it right.
So my ultimate question is, is the Airport dead? Or is there something I can do to get it setup to work again?
I know I don't need to use the Airport's WiFi. I just prefer it to the Zyxel.
Thanks.
AirPort