AP 3700's Not Joining 5760 Controller

[bm_5789]

I am trying to get 25 3700 ap's to join an existing 5760 wireless controller.  There are already 150+ ap's joined and have been for 2+yrs.  I have licenses and the country code is correct.  An ap will appear to join the controller and then disappear from the controller.  This is happening now for over 12 hrs.  

I am attaching the log from the controller.  The same entries appear repeatedly.

[bm_5789]

I took a screenshot of a joined ap3700.  It is the attached.  The 8.2.105.x is the primary software version currently on the ap with the issue.  It should be 10.2.170.

TIA

[patoberli]

I've never seen that version. Doesn't mean it is impossible, just rare.
I sadly don't know any further here, besides maybe manually imaging the AP, but that would take a long time. I suggest you open a TAC.