airport

If you've had an AirPort Extreme for a while, and recently (within the past year or two) had it go missing from your network (when you open AirPort Utility you get 'Device Not Found'), there's a good chance you ran into the same issue I did. Basically, everything was running great, then one day around August 2016, my Extreme disappeared from the network—even though it was routing Internet traffic for all the devices in my house just as good as ever!

The fix?

1. Open AirPort utility (it will likely show "Device Not Found").
2. Unplug your AirPort Extreme, and wait 10 seconds.
3. Plug it back in, and connect to the WiFi network as soon as possible, then immediately go to the AirPort Utility.
4. The AirPort should appear and be manageable (by clicking on it) for a brief period—quickly click on it, click Edit, then clear out any Apple IDs in the 'Back to My Mac' section.

Tonight, after I made a couple changes to my wired in-house Gigabit network (I recently added a few Cat6 runs after moving my main Wireless router—in this case an AirPort Extreme base station), I noticed the Raspberry Pi webserver that was hosting www.pidramble.com wasn't reachable over the network, and Server Check.in started reporting an outage.

I have that particular device set using a DHCP Reservation based on it's MAC address, and it's been working like a champ for over a year. So something was strange, since I hadn't made any networking configuration changes on the Pi itself in a few months, nor had I unplugged it at all in the past month.

I was migrating all the data from a friend's old MacBook (which was running Mac OS X Tiger) to her new MacBook Air (running Mac OS X Mountain Lion), and besides a WiFi hiccup, everything went smoothly (I had to clone the old MacBook's drive to a USB disk, then use Setup Assistant to migrate the data from that disk to the new MacBook Air).

During the Setup Assistant, I could easily connect to my WiFi network, but after the migration was complete, I couldn't connect anymore. I kept getting a pesky error: "Could not join [network]. A connection timeout has occurred." (see picture of error dialog here). Looking through Apple's forums and elsewhere was not much help, because this message seems to be a very generic 'something weird happened' error, happening in many different circumstances.

However, knowing that the keychain and old WiFi connection data from the old Mac had transferred over to the new Mac, and knowing that something might've gone screwy with the network information, I decided to do the following:

I spent the greater part of this afternoon trying to get my AirPort Express to connect to the Internet and share an IP address using a Motorola SB5101 Cable modem (with Charter Internet)... and since the solution was so simple and annoyingly stupid, I thought I'd post it here, for my reference and for anyone else spending an afternoon thinking his AirPort Express is dead.

As it turns out, the cable modem (this one, and likely many others) will only remember the MAC address of the first device it recognized when you last power cycled the modem.

When the Internet went down at my condo yesterday, I turned off my cable modem, plugged my Mac straight into it, turned the modem on, and use the internet via this direct connection for a while. When I plugged the AirPort Express back into the SB5101, I just got a flashing yellow (amber) light, and in the Airport Utility, a notice that the 'Internet Connection wasn't working'.