Best Answer ToxicShock, 09 June 2016 - 06:19 AM
You need to set up your server account on the C&C:Online web site.
This should tell you everything you need to know: C&C:Online User Guide.
Once you've done that, you may find that you need to "hook" to get your game to work with Steam (we are working on a better way of launching these games at the moment). See - I'm having trouble using C&C:Online with Steam. in the Common Issues & Solutions pinned topic.
Go to the full post