CCG Exile Servers require your client to have a number of mods installed to join the server.
The simplest way of making sure you have the correct mods installed is by using the CCG launcher:
CCG Launcher Guide
Alternatively, you could use the A3 launcher. The steps to joining are near identical, you will just have to find the CCG servers in the browser.
If you have any connection issues please work your way through This Guide
Edited by Barney626, 12 July 2017 - 02:56 PM.