Unlike behavior described in article Why AP responds with 404 server error when accessing WebGUI after upgrade to WiNG 5.9?
this might be little confusing.
Out of the box AP75xx seems to be shipped with maintenance release having LEAN image of WiNG 18.104.22.168
If you cannot connect using WebUI (404 - Not Found
) and the AP was not adopted yet, please contact GTACHow to contact Extreme Networks Global Technical Assistance Center (GTAC)