Cisco WAP 551 561 SSID disappearing – Stop Broadcasting

Cisco Wireless Access Points WAP551 and 561 stop broadcasting SSID intermittently, sometimes every day or two.
WAP551 is a Cisco Wireless-N Single Radio Selectable-Band Access Point

Had to troubleshoot this issue for a customer.

We noticed this happening more when WAP radio is configured in 5GHz mode
Issue was caused by a new wireless feature called MFP
Login to the Access Point, go to Wireless section –> Networks. Choose the SSID that is disappearing and Edit. Show Details.
Under MFP make sure “Not Required” is checked.

Make sure you have the latest firmware.

MFP might be available if you have “WAP versions” WPA-TKIP check.  Only Check WPA2-AES.