I was having issues like the alot of you . Was wondering why it was working on my laptop and not desktop.
Search firewall .
Make sure the exe GAME_RELEASE is set to both Private & Public. Boom I got in on my desktop
This worked for me as well, found this on https://www.reddit.com/r/halo/comments/ouccpa/infinite_stuck_on_black_screen_with_three_white/
“After waiting a few minutes, I noticed there was a “dump_tool” subprocess running as part of the Halo Infinite game - I closed that via task manager and a few minutes later my game popped up.
Check task manager and make sure that the game is at least using some CPU, and just wait (or try ending the task I did).”