Bad zip file is unrecoverable :(

To answer the question - try to disable Steam Cloud for Factorio. If Steam is corrupting itself and forgets you have Factorio installed, it might also corrupt the save files it tries to sync with cloud. Or, something is wrong with your drives.


I will use the ...

I'd check the drive generally for errors.
Do you need the save repaired if possible?


I use steam for checking error: no result.
I use a fairly new nvme ssd.

If you can repair the zip, I will consider you as my new god.

edit:
ok, there is a difference in gui, between the steam and the website ...

Hello,

I was playing without problem, then I power off the computer and in the next boot, steam ask me to download the game.

I click install and steam discover the game but download a little file (not the full game) and launch.

when I try to launch my most recent savegame:

Opening zip C:/Users ...