[benher]

Hardware: 2 iMac G5s w/ Tiger 10.4.2 all of the most recent software updates, etc.

Well, they call it "AirMac" in Japan... but it's the same thing.
Over 6 months with no problems and all of a sudden both of my G5s are giving me ambiguous errors about connecting to my AirPort. They can both see the network (apple network xxxxxx) but "There was an error joining the open network..." Not incredibly helpful.

Since both macs failed at once, it can't be a keychain issue (though I tried removing any related entries just to hedge my bets) anyway, it's an open network anyway, so this should be a non-issue.

Could it be that they both upgraded the OS in the background, or Apple's latest software update causes massive internal bleeding inside the chasis?

Of all things, it could be the airport itself, although the LED is solid green and the network shows up on both the macs.

There is no sudden interference from Microwaves or Phones, but I do have zero bars on the reception indicator (though the macs still find an open network.)

I do NOT relish another trip to the Apple store to hang out at their *ahem* "genius bar" so I can get a Japanese-style polite non-answer.

This is a pain.
Any of you other Mac guys feel it?

[ghporter]

Have you done anything to the base station to try to resolve this? You don't give any hint about what model base station you have, so if you don't have the manual handy, I'd just unplug it for a while to reset/reboot it and see if that changes things.