After a visit from the cable company and trying two different cable modems, my Airport Express is flashing amber and the Airport Utility has "Double NAT" in the status line. However, the internet on all devices (computers, iPad & Apple TV) is working. Should I reset the Airport?
MacBook Pro (Retina, 15-inch, Early 2013)
Go to AirPort Utility and select your Express. Click the edit button in the window that opens. Go to Networking and set your Express to Bridge Mode instead of DHCP and NAT. It seems your cable modem is set to provide these services. If this doesn't work, provide the make and model of your cable modem and name of cable company.
Should I reset the Airport?
No, you should do the following, assuming that your Mac is running a newer operating system like Mountain Lion, Mavericks or Yosemite.
Open Finder > Applications > Utilities > AirPort Utility
Click on picture of the AirPort Express
Look for the setting for Status and click on the small amber dot there
That will open up another window that explains the issue.....Double NAT....along with a suggestion to remedy the network error by configuring the AirPort to operate in Bridge Mode.
Or, if you want to try to run the AirPort with the Double NAT error, you do have the option to click to "ignore" the error, and the light on the AirPort will turn green. Strangely, if you call Apple Support, they will likely tell you to ignore the error. I do not recommend that you do this.
Thank you. This solved the problem of the flashing amber. All is OK with the Airport now. Maybe you can help with one more problem. When I plug a cable directly from my Thunderbolt port to one of the ethernet ports on the cable modem (and turn wifi off on my computer) I cannot get a connection to the cable modem. I would like to do this as a backup in case my Airport bites the bullet. Do I need to change something in my Network settings? The cable modem is a Motorola Surfboard SBG6580.
Thank you. It worked. UGADog gave me the same response, and obviously you were both right.
I think you must have meant to say that you were using a Thunderbolt to Ethernet adapter connected to your Mac, which in turn connects to an Ethernet cable coming from one of the four LAN <--> ports on the Motorola modem/router.
I assume that you have a good Ethernet cable as well as a good Thunderbolt to Ethernet adapter.
Remember to restart your Mac once you have made the connection and turned off the WiFi on the Mac.
I think you must have meant to say that you were using a Thunderbolt to Ethernet adapter connected to your Mac, which in turn connects to an Ethernet cable coming from one of the four LAN <--> ports on the Motorola modem/router. Yes, that's exactly how I connected to the modem.
STOP THE PRESSES. I think I just solved the mystery. I just used this cable to connect to an older MacBook with an ethernet port (no Thunderbolt) to the cable modem without wifi and it works fine. So either my Thunderbolt to Ethernet adapter is bad or BOTH my Thunderbolt ports have stopped working with ethernet. However, both Thunderbolt ports work find for video out. I'll order an new adapter and go from there.
Again, thank you for your help.
Airport Express is flashing amber.
