I've had to replaced my failed U6 and am I'm having toruble getting it working - in fact I can't discover the IP address to do anything.

In the past I've used the UniFi Discovery Chrome Extension but this doesn't seem to be availble any more. 

I read somewhere to use WifiMan on my phone to discover but this doesn't find anything on my LAN.

The U6 is connected to the LAN through the supplier PoE adapter.

What am I doing wrong?