1. Make sure you have a stable internet connection, and pause any outside downloads or uploads.

2. Double check that you have the latest version of the map; use the Steam workshop version if possible, as these are usually the most up-to-date. If you plan to use a certain version, make sure that all your players know which it is. Map string consistency errors come from the server (you) having a different map version than the player getting the errors.

3. Disable as many mods as possible, to ensure that all players can successfully connect. Keep any game play mods that you want to show up in the game (eg super hordes, extra ammo mods, etc), but try to avoid anything extra, as host mods can occasionally prevent other players from connecting. Restart the game if you disabled/enabled any mods.

4. Now that you're ready, go and start a locally hosted lobby with a standard campaign map; set this lobby to friends-only so no one can connect while you're configuring the settings. In console, type this command and press enter:

• sv_consistency 0

This means that people who have mods different from yours can connect (non-map string consistency errors come from neglecting this command).

5. With the locally hosted map still being a standard map, start the game. Using a stock map will make sure that the settings are correct, and, most of the time, starting the game this way will fix any trouble others have with stuck loading progress.

6. As soon as the standard map loads, start a vote to return to lobby, and from there change the map to the custom map you want- and be sure to take the friends-only permissions off if you want a public game. The game should now have the correct settings to work.

Here are some other helpful links for doing local servers:

Fixing and preventing consistency errors

Installing mods in Linux, so you Linux games can host your own custom campaign games. [url]A little extra: using a custom MOTD