Yes, part of what it's called "Battleye" a detection software for those cheating in multiplayer mode, if i were you i wouldn't recommend to use the trainer except campaign / story only, pure logic. Anyway i believe current trainer is outdated and while it's unsupported for now, i suggest to read @Mouse84 path.does ARMA 3 1.86.145229 and 1.88 has anti-cheat built-in?
game crash after a minute trainer is activated
plaese make the trainer for V1.90New trainer added.
plaese make the trainer for V1.90