I installed a Unifi AP AC Pro in the upper floor of the house and back to my ASUS router in the basement.  I'm running Win10 with IE, Chrome and FF, but I keep getting a SSL certificate error when trying to run the UniFi software controller so I can configure the AP. An internet search showed this is a common issue but the solution appears way over my head.

SSL Key    

Can someone explain this so a dope (me) can get this thing working?  TIA.

ETA - I configured an exception in FireFox and can at least get into the UniFi configuration software.

ETA II - Wow, this thing is the bomb!  I have it on the second floor firing down and it fills the house with a 5G signal.  I actually had to turn off the radios in the ASUS RT-AC88U.  I did a speed test and was getting 85mps up and down, which is the same speed I'm getting over a wired connection.