After updating my Server from 14w08 to 14w10b all players on the server lost all items in their inventory. The achievements somehow are still available and not lost.
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Comments 3
Isn't it possible to convert the player data to the new format?
Because now we have to go back to an old snapshot and have to put the items from the inventory in a box. And all of the players on a server have to do it at the same time, to update the server or every player has to put it back in a box before he logs out.
I too had this problem, I hope for your sake you made a backup.