Far Cry 4

Can these achievements be unlocked in co op?

no, Campaign only (as said in the achievo's description)

Achievement did not pop for me? Did it pop for you right away or little while after...?

Same for me.

I completed these main missions:
- liberate first bell tower
- help golden path retrieving 2 supplies
- rescue hostages in a village
- liberate your first outpost

But no achievement. Even done the next quest after these four. Didn't help. Is there a problem with achievements not unlocking? Tread Lightly didn't unlock for me either even though it said in the aftermath screen no alarms went off. When should this one pop exactly?

Didn't pop for me too, like "Tread Lightly".

Same here I have earned a few achievements but not 1 has unlocked hmmm.

Tread Lightly did not pop for me as well. Microsoft really needs to step their shit up because every game on the Xbox One I have has had problems with achievements not unlocking when they should some not unlocking at all. Achievements not popping when they're unlocked should not happen on the Xbox One. It should be a key function and effortless. With all the issues on the Xbox One this shouldn't be one of them. They need to fix this issue especially because I'm already frustrated enough with the console.

Hi guys: I confirm this poped up immediately after the message "Act I complete" (or something similar).

I experiment other kind of bugs: incredible long loading time... need to change app and then return to FC4 to play...

you guys are right: there's a lot of glitchs around this new console...

"Welcome to Kyrat" and "Tread Lightly" pop this morning for me

Sometime I found that some achievements never popped up, but are actually unlocked if checked in the achievements' list...

mah..

So for anyone reading this in 2020, just check to see if the achievement stealth/ghost popped. I thought it wasn't happening for me, but it did, it just didn't come up on the screen.

If it doesn’t pop for you on the first try after I 100% the game I restarted and after I did Act 1 again it popped.

Mine didn’t pop so once I’m done with everything else. I’ll cycle back round and replay this and see if it’ll pop. (and saving the 15 hostages, at 20 now and nothing)

Yea same here thankfully they popped for me this morning as well. Now if I can get Watch Dogs to do the same so I don't have to start the game over just for the achievement at the beginning of the game that didn't pop. Didn't realize this until I had everything done in the game.