Hey guys,
i have met with this problem while using my iphone 5, others said that i bought the off-brand cable.
and there is code in iOS 7 that tells the firmware if there is an authenticator chip in the charger and only Apple USB chargers has this chip.
to fix this problem when you plug in an off-brand cable and a warning pops-up, you can do as the following:
Method 1:
Plug the USB cable to the wall-charger
Turn off the iPhone and when you see the loading wheel spinning, plug the charger in the iPhone
Let the iPhone be connected to the charger for a while. Don’t switch it on
After about 15 minutes, turn it on your iPhone. Dismiss the warnings
The charging should mostly continue without a problem
Method 2:
Plug in USB power to wall-charger
Then connect USB cable to iPhone
Dismiss any warnings
Unlock your iPhone so you get to the “Home Screen”
Dismiss any remaining warnings
Unplug the fake “Knock Off” USB cable
Followed by plugging it back in.
Dismiss warning again
It should now charge.
i did as the above method, and works fine. lucky you.