startup.log:
I also tried upgrading to 1.1.20, but same problem.0.736 Error ServerMultiplayerManager.cpp:91: MultiplayerManager failed: "Map version 0.17.79-0 cannot be loaded because it is lower than the minimum input version (0.18.0-0)."
Update history:
Created server 0.17.79
Upgraded to 1.0.0
Upgraded to 1.1.19
Upgraded to 1.1.21 #failed
(after each upgrade the game has been played extensively)
How should this be fixed?
Solution:
remove old maps from the /saves directory if your server starts with --start-server-load-latest.
My server is configured to uses autosave and the server is started with the --start-server-load-latest option. This results in an auto save every 5 minutes and will create several files who's name start with _autosave. When the server start, it will take automatically the most resent saved map file. But before the autosave was configured there was also a map file, it is still in the directory as it is not automatically removed. That file is only used the first time when the server start, it will never be used again, as it is the oldest file and will never be overwritten. So far no problem. But apparently the Factorio server does not use file timestamps to see what file to load, Factorio is checking each file before starting and that's a problem, as from 1.1.20 it no longer is able to read the file formats older than 0.18.0. Solution, remove those old files from the /saves directory.
