There is a bug in single player survival mode that causes you to not be able to open your storage chests after a few in-game days and after you save the game and come back later. You lose everything you put in them. It also happens to the furnace and brewing stand. You have to tear them down and rebuild them to use them again after a save and you lose anything you left in them also. Please fix this bug, it is making the game very frustrating and almost no fun to play at times!
dont use chests = fixed
then dont play it the admins are fixing this stuff
use an axe Duh
I think that the problem is that mining the chest in that mode won't drop the items in the chest, thus loosing everything stored into it.