Hi there..
downgraded WLC to get it into (EoL) WCS to 7.0.230.0.
The Access Points (3502i) downgraded also to 7.0.230.0.
After adding the WLC to our old WCS i upgraded WLC back to 8.3.150.0.
Most Access Points upgraded successfully - but SOME not.
They apear shortly in WLC Webconsole "downloading", but then disapear and start again.
Only way to get the APs back to work is to do factory reset (mode button).
Tried all debugs and read FAQ why ap does not join wlc - no success.
ideas? Thank you!!!