I tried with clean account and all mods removed. Same problem.

Having same issue - no love from devs here??? Don't understand the reference to changing profiles or -profiles option, though.

ARMA3 stores user's profile in home directory. You can delete it and Arma will create a new one. Or you can add -profile switch to Arma launch options to create one with a different name (by default it's name of your account). I did it to make sure that starting with a new profile fixes the problem and that it's not caused by bad configuration.

On the happier note: I manually edited config files (somehow) and launched A3 in a window (added -window to launch options). But now it sometimes hangs on before the intro is played and only the black screen is displayed. I think my hybrid graphics (integrated Intel + discrete nVidia) is to blame.

We can't reproduce this issue on any our Mac. Arma3 keeps data path "~/Library/Application Support/com.vpltd.Arma3/GameDocuments" ('~' is users home directory). It may be some file system issue, on Mac there is tool "Disk Utility" which can repair file system issues. To check folder privileges use Finder and go to mentioned path and choose 'Get Info' from context menu and then check 'Sharing & Permissions' (should be Read & Write).

Had some faults with my hard drive and they were repaired with Disk Utility without too much of a problem. Verified game files on Steam, all ok. Still produces same fault. Can I provide more information for you?

Hello, I'm having exactly the same issue on:

MacBook Pro (Retina, 15-inch, Mid 2015)
2.5 GHz Intel Core i7
16 GB 1600 MHz DDR3
AMD Radeon R9 M370X 2048 MB

El Capitan 10.11.6

Symptoms:
Any attempt to load ArmA 3 on Mac OSX, with user profile data saved to the ArmA 3 GameDocuments location, results in the loading screen hanging at "Loading Profile". Force quit (or kill command) is required to escape.

Specifically, the game loading screen will hang if the .Arma3Profile and the .vars.Arma3Profile data are present in the GameDocuments location.

It is possible to load ArmA 3 with a Save folder within the GameDocuments location, so long as any .Arma3Profile files are deleted prior to launch.

Workaround:

• Remove all profile saves from ArmA 3 save location. The quick and blunt way is to remove the profile named folder from Arma 3 - Other Profiles, in Terminal:

rm -rf  /Users/[USERNAME]/Library/Application\ Support/com.vpltd.Arma3/GameDocuments/Arma\ 3\ -\ Other\ Profiles/[profile name]

• Start ArmA 3 again and start from scratch. :(

This workaround allows for ArmA 3 to start again, at the price of the profile saved data. It does not resolve the issue.

Attempts at resolving the problem:

Following the advice given by QA_Sec Nov 6 2015 fails to resolve the problem. Steps attempted to resolve the hanging loading screen with previously saved profile data:

• Ran the Disk Utility (passed), ran ArmA 3 - Loading Screen Hangs. Fail
• Ran the Disk Utility (passed), Verified the Game Files through Steam (passed), ran ArmA 3 - Loading Screen Hangs. Fail
• Attempted the Steam Beta development build ;) heheh. FYI, this does not work on OSX! And I had to re-download ArmA 3 entirely :(. Fail
• Ran the Disk Utility (passed), Verified the Game Files through Steam (passed), force Read & Write on the Save File location, in Terminal (see command below), ran ArmA 3 - Loading Screen Hangs. Fail

chmod -R 777 /Users/[USERNAME]/Library/Application\ Support/com.vpltd.Arma3/GameDocuments

Conclusion
This issue is not resolved, please can someone give us some pointers on how to debug it for you?
There are no crash logs from this error, since the game just hangs at initialisation.

Could it be a File Ownership issue (chown)? - The Arma3Profile files are owned by the current user. Does Steam (and therefore ArmA) run as the current user, or a different user?

I don't think that this works: Moving the profile files out of the Other Profiles folder and then once the game is launched, move them back in again. But I haven't tried.