How to properly convert Single saves to Multiplayer saves ?

[flow969]

Hi everyone,

I tried to convert my Single save to Mulitplayer save on my Cuberite server but it is not correctly 'converted'.

This is what I've done :
1) Made a back up of the 'world' folder
2) Delete all files from the 'world' folder
3) Copied all my single save file into the empty 'world' folder

Everything works except for my inventory (players_data.dat files)

Someone know how to make them work please ?