Are you connecting to an actual Airport Extreme Base station or is it a wireless router from another manufacturer?
When you say cannot select, do you mean that the option is greyed out or that there is not option there or that when selected, you cannot join the network?
Is there any security on that wireless network?
P
I have just bought a new MacBook (10.5.2 2.4MHz 2MB RAM).
I can't seem to be able to select a preferred wireless network even after selecting my own Airport network in the Network preference advanced.
Every time I start-up or wake-up I have to select it again.
Any suggestions?

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