i also had this, it showed a
"WARNING: User Panel possible issue detected! If you have issues with user panel login, CSF Firewall stop/start will be needed."
I did that, completely. and it worked.
Hope that helps.. as i only received this error message briefly.
so, STOP (dont just restart) CSF Firewall.. Then START it.. Wait
I think i did it twice. but it solved it at once.
Cheers
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