Blocks and items disapearing after an unplanned server shutdown

[Syderal]

Title:

Desynchronisation ?​

Launcher Version:

1.7.10​

Modpack:

Infinity Evolved​

Modpack Version:

1.7(v2.3.5)​

Log Link:

​

Details of the issue:

We started a server with a friend 4-5 days ago and everything was working fine but this morning the computer from my friend ( who is hosting the server ) did a windows update and rebooted automaticly while the server was up. We restarted the server with "ServerStart" and when we are ingame blocks from mods just disapear when we click on them.
We tried few thing :
-relaunching the serv > same problem
-relaunching with a "world" backup
-downloading the ftb server again and creating a new server where we put our "world" folder in it (or even with a "world" from backups folder) but everytime the blocks are disapearing or we can use the block but everything linked to it is just gone : For exemple > wooden storage crates are empty, the ender io pipes are here (we cant pass trhought them) but we dont see them and even with the cursor on them the game doesnt show us the name of the pipe.

So can someone explain us whats happening and if there is something we can do or try to do to repair it ?
Thanks

Edit 1 : for what i have seen on forums that may look like a serv desynchronisation. When we were trying to solve the probleme the game sometimes kicked me for "flying" whereas i was on the ground. What do you guys think ?​

 

[Syderal]

Its been a week now and still no one replied. Its not like im the only one that encountered this bug before from what i have seen during my recherches on google. Is there really no one who knows whats happening ? Because when i use a non corrupted backup save on a brand new folder with a new server inside and its not working, this mean that not everything from the world is saved into the "world" folder. So where is this saved ? i guess someone here should know this right ?