How to Factory Reset an Airport Extreme
1. Unplug the power cable from the back of the Airport Extreme. Locate the reset button. The reset button is just to the right of the power port.
2. Insert a pin, pen, or paperclip end into the reset button found on the back.
3. While holding the reset button in, reconnect the power plug into the male socket on the back of the Airport Extreme. Do not remove the pin, pen, or paperclip from the reset button.
4. Keep the reset button depressed for about 6 seconds or until you see the light on the front of the Airport Extreme flash rapidly. The color should be an amber color.
5. Wait about a minute for the Airport Extreme to restart.
6. You can launch Airport Utility to re-configure the Airport Extreme.