Cool Wireless Access Point Logs Error After Tablet Turns ON

My Cisco Wireless Access Point WAP4410N logs the following error most of the time after I turn the tablet ON:
hostapd: ptk update fail
I have no idea what that means. It has been happening ever since I got the tablet 4 weeks ago.
This seems to happen at the time the tablet makes a WiFi connection after power up. Does not happen when the tablet comes out of sleep.