AirPort Extreme Setup Glitch
I have a long established AirPort network based on an AirPort Extreme A1521. The network was set up with OS 10.13.6. It works just fine with (now) OS 12.6 except ...
I am setting up another AirPort Extreme to work in the network and AirPort Utility (v 6.3.9) will NOT accept the password for the network to do so. I enter the password in the dialog box, hit "Enter" and it just recycles back empty.
What am I missing here?
Mac mini 2018 or later