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One found solution

I was having this issue -- many of the issues described in many of your comments. When I opened "Network Preferences" through my airport icon at the top, I did the following:

1. Clicked on "Airport" on the left pane (there may be other options, like, Bluetooth, FireWire, etc.)

2. Clicked the "+" symbol, then selected the INTERFACE as, "Airport," and allowed the SERVICE NAME to remain, "Airport 2."

3. I clicked "CREATE," and when Airport 2 went live it connected no problems. I simply deleted the old Airport Interface, and so far so good.

NOTES: I have put the computer to SLEEP, but have not SHUT DOWN or RESTARTED. I will leave a follow up comment if, and only if my "solution" does NOT work upon restart.

Hope this helps!
 
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