PBEM = Play By EMail
This is directly from the manual, updated by myself to fit to the current game.
Play by Email (PBEM )
CW II can be played against another human opponent using PBEM or any other valid file transfer protocol, such as Instant Messaging. One of the players (the “Host”) will have to initiate the game. The procedure is detailed below:
1. Create a game:
The Hosting player chooses a Campaign/Scenario and a side and starts the game as usual. This automatically generates a sub-folder in the 'C:\Users\{Username}\My Games\Civil War II\CW2\Saves\' directory, named after the Campaign or Scenario selected ('1861 April Campaign' if you play the “1861 April Campaign” scenario, for example). Please note that a number at the end of the folder name helps differentiate between multiple instances of the same Campaign/Scenario. However, the best way to avoid confusion is to rename the in-game Save (e.g. 1861 Campaign John vs. Joe). Do NOT rename any CW2 files inside the Saves\{scenario_name} folder just created. They will be changed automatically when using the rename function in the load-scenario menu.
In this newly created folder you will find a .hst file, which is shared by both players.
2. Host sends the HST file to opponent:
The Hosting player now sends his opponent the .hst file. The opponent must create a folder in the 'C:\Users\{Username}\My Games\Civil War II\CW2\Saves\' directory, named after the Campaign or Scenario exactly as in the .hst file name, and copy the .hst file into this folder. For example, if the full name of the .hst file received is '1861 April Campaign.hst', the non-hosting player must create a folder named '1861 April Campaign' and copy the .hst into it.
Note: In order to avoid possible data corruption while transferring files, it is strongly advised to compress the file(s) into an archive format such as ZIP, RAR, or 7z, what ever the players agree upon.
3. Non-Host sends ORD file to Host:
Each player now loads the scenario .hst file and gives his orders for the upcoming turn. When ready, each player saves the game. This will generate a .ord file in the folder mentioned above.
Important: do not click on End Turn at this step, only save.
The Non-Hosting player then sends his .ord file to the Hosting player.
4. Host resolves turn
The Hosting player saves the .ord file received from his opponent into the appropriate directory and loads the game again. He now clicks on End Turn to launch the turn resolution, where all orders are then executed. A new turn is now
ready to start. Go back to step 2. and repeat, only the non-hosting player will use the previously created folder instead of creating a new one.
Note: The Non-Hosting player doesn’t get to “play back” his opponent’s turn. However, he can check the turn’s Message Log to see what has occurred during the turn, including battle reports.
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Maybe this could be sticky-ed for posterity.