so the last thing you can do is to contact with 1c support.

If you have a out of sync error it basicly means there is a corrupted file, or something like a multiplayer map has been edited. I have the same problem, let me know when you find a fix.

@Velineon
what version d y have? steam, hardcopy, gamersgate...?
have y installed patch 1.16.4 in correct gamefolder? and are y running game with "outfront_mp.exe"?

after deinstalling game, have y deleted .../Men of War/... gamedirectory manualy with windows explorer? reinstalling game needs an empty .../Men of War/... folder.

@Velineon
what version d y have? steam, hardcopy, gamersgate...?
have y installed patch 1.16.4 in correct gamefolder? and are y running game with "outfront_mp.exe"?

after deinstalling game, have y deleted .../Men of War/... gamedirectory manualy with windows explorer? reinstalling game needs an empty .../Men of War/... folder.

It is the Steam version.
The correct game folder is "steamapps/common/men of war/" correct? I install the patch somewhere else and then copy the files into that. It overwrites some old ones, and adds other new ones. I use the "outfront_mp.exe" to launch it. However, I have not deleted hte Men of War game directory when I deinstalled it. I will try that this time and let you know how that goes.

i made following experience:
after testing mow-editor (eg. loading map & changing weatherfiles or other things) i have verry often "out of synch" errors because mow-editor save "new" files in ...men of war\resource\.... and game allways load this files.
make shure that all "new" mow-editor-files are deleted/moved from ...men of war\resource\....

deinstalling game normaly dont delete these mow-editor-files.

Okay, finally got it to work! The fix that worked for me was to uninstall it on Steam, and then go to the directory /program files/steam/steamapps/common/men of war/ and delete the "men of war" folder completely. Then install the game again ,and it worked!

congratulations!!

I'll be trying again to fix my out of sync error sometime today.

Update: I just reinstalled Men of War, deleting everything. I still get the same out of sync error when trying to play multiplayer. I could not find the folder to delete the maps I edited.