mrwynd: Online multiplayer is still possible but you need to do some changes.

CD KEY Note: When you run this for the first time you'll come to a splash screen with "buy cd key"

You'll be directed to this website to request a key, this will most likely fail - http://www.massgate.org/cdkeys/

If it fails you need to go to the WiC Discord channel and request a cd key

Go here to request a key: https://discord.gg/r48Qpp

Go to this website for the online patch and instructions http://www.massgate.org/multiplayer.php (I've copy/pasted the instructions below)

Install World in Conflict from GOG using the GOG Launcher.
After installation, your game should be at version 1.011.

Download and apply the World in Conflict Online Multiplayer Fix. This is required in order to
connect to our multiplayer services.
As the executable installer won't find the game in the GOG path, you will have to perform a
manual install. Download the .zip-package and extract the files. Copy the 'dbghelp.dll' file
and the 'wic.exe' into your World in Conflict root folder (for GOG versions, that should be
"C:\GOG Galaxy\Games\World in Conflict - Complete Edition") and overwrite the existing files.
You may need admin rights on your PC in order to do this.

In your World in Conflict root folder, look for the file 'assault.dat' and rename it to something else,
e.g. 'assault_original.dat'. NOTE: This will disable the Soviet Assault content - if you want to play the
campaign with the Soviet Assault missions, revert the name to 'assault.dat'.

It's very important you change this filename or your CD key will not be valid!!!!

Create your ingame account. Launch the game, enter the CD key you received from massgate.org
and click 'Multiplayer' in the menu. Click 'Create Account' and follow the instructions on the screen.
You will have to use the same e-mail address that you used to request the CD key. Create a
new profile with a unique name.