I changed my internet box and now my airport extreme light flashes amber what I need to do to get the green light back

Question

I changed my internet box and now my airport extreme light is flashing amber but I have internet connection, how can I get the green light back

Answer 1

When you change modem (the internet box I presume) you should reset the AE to factory and redo the setup completely.
However if you merely want to stop the amber flashing.. find the cause.
Open the airport utility and click on the AE..
It will give you a list of faults or problems... fix each one and the light will turn green.
The most likely fault is double NAT.
That means the AE should be in bridge mode.. but if you list the fault we can give you further help with what to do to fix it if you cannot understand the instructions.
Apple does give a procedure to remove the problem although it may not always be the best solution.
eg Ignore.. the light will turn green.
Lately Apple is saying to use double NAT and ignore the problem.. I do not thing that is a good idea at all.
To bridge however may be easier after a full factory reset than trying to do a change to the setup.
If you run Yosemite.. then I recommend the following.. please read AE for TC.. (Time Capsule is what I mainly use but the setup is identical).
Factory reset universal
Power off the TC.. ie pull the power cord or power off at the wall.. wait 10sec.. hold in the reset button.. be gentle.. power on again still holding in reset.. and keep holding it in for another 10sec. You may need some help as it is hard to both hold in reset and apply power. It will show success by rapidly blinking the front led. Release the reset.. and wait a couple of min for the TC to reset and come back with factory settings. If the front LED doesn’t blink rapidly you missed it and simply try again. The reset is fairly fragile in these.. press it so you feel it just click and no more.. I have seen people bend the lever or even break it. I use a toothpick as tool.
N.B. None of your files on the hard disk of the TC are deleted.. this simply clears out the router settings of the TC.
Setup the TC again.
ie Start from a factory reset. No files are lost on the hard disk doing this.
Then redo the setup from the computer with Yosemite.
1. Use very short names.. NOT APPLE RECOMMENDED names. No spaces and pure alphanumerics.
eg TCgen5 and TCwifi for basestation and wireless respectively.
Even better if the issue is more wireless use TC24ghz and TC5ghz with fixed channels as this also seems to help stop the nonsense. But this can be tried in the second round.
2. Use all passwords that also comply but can be a bit longer. ie 8-20 characters mixed case and numbers.. no non-alphanumerics.
3. Ensure the TC always takes the same IP address.. you will need to do this on the main router using dhcp reservation.. or a bit more complex setup using static IP in the TC. But this is important.. having IP drift all over the place when Yosemite cannot remember its own name for 5 min after a reboot makes for poor networking. If the TC is main router it will not be an issue.
In your case bridge is most likely required.. and it is up to you how you deal with this one.. for now see if it is stable.. if it gives you issues come back and fix it.
4. Set IPv6 to link-local only on the computer..
This is strange one in that apple should have fixed this up ages ago.. but we are finding the auto setting even on Yosemite is still giving the wrong setup.