last time i tried i was able to pack my miliatry tent.
when you tried, you might still have had an invisible item left, that blocked your attemts. in that case, relogging usually makes it show up.

I've been having the same issues over multiple persistant public servers. - Although I didn't try to actually put the tent on my back, I was unable to pick it up into my hands, or to roll up tent once it was already pitched by another player. My friend that I was playing with had the same issue.

From my experience,
only the player who pitched the tent can pack the tent.
I don't know if you can pack the tent if your character dies, but i think that you cannot.

Lately it seems tents can only be packed when hands are empty and tent is empty. This makes sense. Perhaps we will see an animation for this in the future which would fill in the missing link here?

Military tents cannot be carried in the hands, not sure if this is a bug or not. Have not tested other tents in hands on .60 yet but in .59 it worked.

It's neither about the invisible loot outside, nor about the fact that it belongs to another player. It simply cannot be packed up. Also it randomly changes its position after server restart.

Seules les car-tents sont repackables apres un restart serveur. Par contre en sortant d'une tente civile et en me placant à gauche de la porte, j'ai eu plusieurs fois la possibilité de "repack the tent", mais je n'arrive pas à reproduire cette action de façon reguliere...