Airport extreme can not be recognized?, Airport extreme can not be recognized?, Airport extreme can not be recognized?

My Airport Extreme Station (4th Generation) is all of a sudden not recogized by the Airport Utility Software. I rebooted the Airport Extreme device a few times, disconnected it completely, and did it set it back to the factory default setting. No recognition. I tried configurating it with all my devices; IPhone 4S, IPad, MacBookPro and new iMac. Always the same message, even though I have internet access through the Airport default Wifi-ID. So the the Airport device works properly. Just no access for configuration, Does anyone has an advice to get back into the Airport Set-up through the Airport Utility program? Thank you.