I know, that there is a bunch of achievements broken in Halo MCC campaign. But, Im starting to think we have to blame the achievements app, and not the game.

Some achievements in Halo campaign are taking a long time to pop or unlock. Some just dont pop, but unlock. Yesterday, I was playing the new GoT game (nice btw), and I finish the game in one sit. Just after that, I open the achievement app to see if that game had achievement, because none of it pop it. And there they are, all of them unlocked. Same thing happened in D4.

It take the taste away from it. We all want to see the achievement pop. Some Halo achievements just unlocked to me, but didnt pop either. Maybe, the problem is not the game, but this stupid achievement app we have in the Xbox One.

Well... Someone else have notice this?
I've had 9 achievements stuck in the "Done... Unlocking!" phase for 4 weeks now (note: they haven't unlocked and I haven't gotten the GamerScore for them)

I want my 90g and the avatars to go with them.
I had some par times achievements stuck in Done... unlocking for a few weeks, but after a couple of the more recent patches I went and re-did them and it gave them to me immediately.
I had some par times achievements stuck in Done... unlocking for a few weeks, but after a couple of the more recent patches I went and re-did them and it gave them to me immediately.
OMG really? I might try that aswell, still miss the truth and reconcilliation one
I got something to add... My achievements for the whole Halo 2 Legendary done on campaign did not unlock at all (same for Heroic).

But the game itself says I finished the game on "Normal", although in the mission selection screen, every missions have the Legendary logo.
It's actually Halo waypoint since it doesn't register missions correctly. Like claiming I completed with a high score, doing it 0 seconds, yet having no skulls attached.
I came here looking for something similar. from what i understand is that the Achievements on the Xbox One are done differently to the 360 version where it is all done on console. But the Xbox One version seems to be

"Complete Criteria to unlock > Sends info to "X" Server > Authenticates Achievement > Sends info back to console to unlock"

I came to this conclusion from a small quote on the Xbox website which states

Note You must be connected to Xbox Live to unlock an achievement and earn boost your gamerscore. If you complete the requirements for an achievement while you're offline, it will unlock as soon as you connect.
This pretty much says that the achievement needs to be verified before it unlocks.

Now i am either thinking that it is an issue with this system that verifies the achievement or it is an issue with the game itself or even both.

My achievement "Veteran" was suppose to unlock after completing all campaigns on normal but the tracker in the game states I have completed 27 out of 40 missions on Normal which i know is incorrect as i have completed all missions on Normal through all campaigns but yet achievements such as "The Long Haul" track i have completed 41 out of 500 missions or multiplayer games and since i have not played the multiplayer yet its clearly tracked that i have completed 41 campaign missions but there is a total of 46 missions including the cut scene missions and only 40 actual missions. Also i have not unlocked any of the separate achievements for completing each level on Halo 2 and the Blast soda cans wont unlock for me either.

So I am drawing a conclusion that the real issue lies within a combination of the Achievements App/Server Verification and the Game not correctly tracking the criteria. At the moment most of my bugged achievements seem to be confined to the Halo 2 part of the game from what i can tell.
Yes. So looks like all this achievements confusion have a direct link with that stupid "always online" policy Microsoft tried to use prior to Xbox One launch. I already experience at least one achievement problem in every campaign. Thats why I give up on beat the game on legendary. I will wait till all this confusion is in the past (if ever...)

And there is no way we can rely on Waypoint to register al our campaing data. I lost count how many times I beat the obnoxious "Forerunner" level in Halo 4 (the 360 game)... I did it in every way possible. This stupid site still register it as never played. And prevent me to unlock armor in Halo 4 multiplayer.

Achievements... one of the best ideas Microsoft have in the last generation, its a pain in this new gen. The achievements app works poorly. Im almost giving up on the matter.