I used to play ArmA a lot but quit and left it for months.
When I came back, I noticed that I couldn't get the game to open without crashing to desktop. It would happen after the splash screens, when the main menu should have happened.
I've tired:
Verify integrity of game cache
Deleting the ArmA 3 folder in Documents to regenerate cfg files
Deleting ArmA 3's appdata folder
Reinstalling my GPU drivers
Reinstalling my motherboard drivers
Unplugging all USB devices except mouse/keyboard
Completely deleting the ArmA 3 steam folder and reinstalling
Reinstalling all the redistributables
Praying to Bohemia Interactive
I have attached the RPT and crash dump files.
It worked perfectly around 6 months ago when I played. No major hardware changes since.