following the instructions that came with it.
The blinking yellow light indicates that it is not seeing the base station, or the rest of the network.
Could be due to a security problem that you created when you configured the wireless security.
P
After configuring wireless security on my Airport Extreme base station, the Airport Express I use to stream iTunes music to my whole-house stereo system has disappeared. Airport Utility can't see it. Yes, I checked connections. All I get is a blinking yellow light on the Express. The base station works as its supposed to.
I have a 17" Powerbook G4 with a 1.33 GHz Power PC processor. I'm running MacOS 10.5.8

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