Hello,
could you please manually gather Launcher logs and upload them: http://arma.jiripolasek.com/howtos.html ? I believe that the issue is not directly caused by corrupted settings, but some other component on your system that prevents the processing of configuration files.

Before that I'd suggest to verify integrity of the game cache, to be sure the game is all right:

1. Open Steam.
2. From the Library section, right-click on "Arma 3" and select Properties from the menu.
3. Select the Local files tab and click the Verify integrity of game cache... button.
4. Steam will verify the game's files - this process may take several minutes.

Hello,

Currently experiencing this problem as well.
I'm using Nvidia GeForce Now to run steam to run Arma 3, so I don't have access to system files.
I've tried verifying game files through steam menus, to no avail.

Any solutions on this?

Hello @captaincullen, sorry to hear about your issue.
To be able to check what the cause might be and to fix it you would need access to the "system files".
Maybe GeForce support can help you out?