Some good guidelines here if you are new to this.  Thanks for the help Jolly Giant. “try a factory restore of the AX. pull it from power and use a paperclip or pointy object to press the reset button @ the back of the unit. keep it pressed, while you plug the unit back into the outlet, until the status light flashes amber rapidly (8-10 seconds).

when the AX restarted it will have created a new, separate network so airport utility (AU) won’t be able tosee it yet. click on the airport icon in your menu bar and look for apple network 11c3fg or similar. in order to set the AX up you will have to switch networks @ the prompt.

now AU should pick the AX up and you will be able to configure it as desired.”