Uninstall the "CryServ-Client" if you have that listed under Add/Remove programs.
All you need is to extract the attachment, into your drive location, where your Crysis Wars is located. for me that is D:\Program Files (x86)\Electronic Arts\Crytek\Crysis Wars\Mods
By that I use a short cut as it is below:
"D:\Program Files (x86)\Electronic Arts\Crytek\Crysis Wars\Bin64\Crysis.exe" -mod CryServ-Client
But, if you see an error while connecting and says that you need an update version, you have to delete the content in the 'CryServ-Client' folder. When there is a client update, I will ZIP it up for the manual install (just like above).
I broke my game-pc, but I keep the servers updated and what is going on, by a laptop
CryServ-Client.zip