Can't build lighting - at all [FIXED]

[PascalN]

I'm on OSX, just installed a completely new system with High Sierra.. (GTX 1080) I have installed 4.20 and 4.21 preview 3, and I can't build lighting on any project. Not even a blank new project with a floor and a cube, the progression stays at 0%, and then eventually stops..
Am I missing something ?

[darthviper107]

If you're trying to run with a GTX 1080 maybe there's an issue with hardware compatibility, since it's not properly supported.

[PascalN]

Well it works with 10.12.6 Sierra.. And you have to upgrade to use the latest builds :-/

[PascalN]

Turns out it's a firewall issue (Little Snitch for me), Editor needs to accept incoming connections