Hi Peter,
4 way handshake failure could occur due to multiple reasons, on client or AP/controller side.
You may need to take OTA captures and enable additional debugging on controller/AP and analyse the captures/logs, which may be not easy, if you have limited product and protocol knowledge.
I will suggest opening a support case to troubleshoot this issue.
Regards,
Syamantak Omer
Syamantak Omer
Sr.Staff TSE | CWNA | CCNA | RCWA | RASZA | RICXI
RUCKUS Networks, CommScope!
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