Device Not Found, but internet working

Do you have Back to My Mac configured on the TC with your AppleID?

This happened to me and when I removed my AppleID and disabled Back to My Mac it stopped happening and the TC became visible again.

Hopefully Apple will fix this soon but it would pay to log a support call with Apple about it as well.

To me this started around August 11, after 20:00 UTC. I submitted an online bugreport. http://www.apple.com/feedback/timecapsule.html

This is happening to me.

I have a TC and AE. Both show missing yet both are providing Internet via WiFi.
I see that my last Time Machine backup was 8/9.

Both devices have green lights on the actual hardware.

In Airport Utility both show missing.

I rebooted both. For a time they showed up, in fact it showed a firmware update available and I was able to update them.
But eventually both went back to showing as missing with yellow exclamation points.

This happens on my two Macs on El Capitan and on a MBA on the beta for macOS.

Hopefully they will find this bug and fix it.

Have you also read you can create a work around by disabling the Back to my Mac in the TC and AE? Via the Airport Config tool you can still config them by the menu option Config another device and enter the IP and password. Remove your iCloud ID and restart and Presto!

Thank you MurgenTemplar. I did not know you could use the Configure Other option and although removing BTMM option from the TC did not solve this issue for me at least I can configure some of the other options without Soft Resetting the TC.

I'm sorry to hear that. In my case it worked. I started with the main router (AE) and did the TM afterwards. The reason why the Expres never greyed out was because BTTM was not set in that one. I hope Apple comes with a solution for us all, it is obvious the root-cause is somewhere in BTTM/iCloud.

Just for the record my setup, maybe it is helpful.

Thanks MurgenTemplar, this is a great workaround for my same problem that appears for the first time this morning.

If you disconnect the WAN cable to your modem and then reboot the Airport device, it will appear (and stay visible) in Airport Utility, so you can then take your time editing it to remove the Back to my Mac entries.

I had this issue since Friday last (12th Aug), and fixed it by removing the Back to my Mac entries.

I have this issue also. Removing BTMM did not solve it. The TC is shown while ethernet connected. After I remove the ethernet it changes to device not found, but is still connected to internet and the green light is still on. I have not tried to call support yet, or the cable company.

I'm experiencing the same, if not an identical problem. I discovered it yesterday when I went to print a document using the printer that is connected to the Airport via a USB printer cable. Executing a print command got me a, "printer is not connected" message from the HP printer. All cable were connected and the Aiport light glowed steadily green. Internet service was fine. Calling up the Aiport icon said that the Internet was fine but the router had not power. I unplugged and again plugged in the Airport and everything seemed fine-- for a few minutes. Trying a different power outlet had the same results-- normal briefly and then no power on the router. I suspect that this is a hardware problem in the router but I'd like to know that for sure.

Same issue

Identical problem

I unplugged and again plugged in the Airport and everything seemed fine-- for a few minutes. Trying a different power outlet had the same results-- normal briefly and then no power on the router. I suspect that this is a hardware problem in the router but I'd like to know that for sure.

If you are saying that the indicator light on the Airport is going out, and is not lit up at all, then this is an internal power supply issue inside the AirPort. Unfortunately, not much that you can do about that other than replace the AirPort.

The AirPort is covered for one year, but if you have AppleCare in effect on one of your Macs....and...the AirPort is less than three years old, it is normally covered by the Applecare umbrella. Contact Apple support to get the replacement process going.

Same issue

Same issue of no power, or some other same issue?

If no power, then see the post above.