[0.11.18][slpwnd](x64)Game locks up on M.Player Host exit

[InflatableBeerTent]

After playing a multiplayer game, either via LAN or Teamviewer VPN, exiting the game results in the game hanging.

To replicate:
Start a multiplayer game as the Host.
Allow one or two players to join the game.
Play for 30 minutes.
Allow all teammates to disconnect from the game.
(We all typically save the game before exiting.)
Attempt to exit the game by opening the menu and click "Quit game."

The game hangs and seems to take up a lot of processing time. It takes a few moments for the Task Manager to open, and a few more moments to end the task.

DXDIAG Text file below. Crash dump is not created.
https://dl.dropboxusercontent.com/u/65110350/DxDiag.txt

[slpwnd]

Interesting. Could you maybe post a log file (of the hosting player) for this?

Also is there a way to simulate this without the "play for 30 minutes" bit? I am after as simple reproducible scenario as possible. Neither have I been able to simulate it in my local environment nor have we encountered anything like this in our dev testing.

[satcass]

have/had the same problem since 0.11.17 or so.

for me it turned out to be my firewall (zonealarm), even though i gave factorio 100% permission.
closing zonealarm fixed the problem for me.

it didn't even need to be a game with somebody connected. just opening a game through the multiplayer tab and then trying to exit the game caused the crash.

[slpwnd]

This turned out to be an obscure issue with windows sockets. Also it seems related only to mentioned firewall (zonealarm). Anyway we have replicated the issue, @Twinsen made a fix and now it seems working fine. Working fine means the game doesn't hang on Multiplayer exit. However it is not 100% because the zonealarm firewall has been doing some very strange stuff so if you still encounter this just shout.