Last night I played through 343 Guilty Spark on Heroic with no skulls.
At the very end of the level, during the final cut scene, the game crashed. I didn’t get the achievement for completing the level.
I force quit the game, then restarted it, and resumed the campaign, which put me at the beginning of The Library. So the game knew that I’d finished the level, but crashed when trying to post the achievement.
I’ve tried to play truth & reconciliation time after time but it keeps crashing. Cant unlock the achievement for assault on the control room as well. I beat halo 2 on heroic but didn’t get the achievement for beating it on that difficulty. Also haven’t gotten the achievement for beating regret which I’ve tried twice now. And who knows how long its going to say “done! Unlocking…” For pillar of autumn, Cairo station and outskirts.