I HAVE READ THE HOW-TO THREAD.
Hello there. I have been seeing the same message for some days now.
I was able to connect to KW online in the past and had been playing constantly. I used to run the game on version 1.02 until 3 days ago when I decided to install 1.02+. Ever since then i have not been able to connect. I figured there is no problem with that as I can just reinstall the game and run version 1.02 like before. But as of today I have reinstalled the game several times and no configuration seemed to fix the issue. Weirdly enough I am able to connect to Tiberium Wars online though. My version of the game is the normal one (not ultimate collection nor first decade) and my OS is Windows 7. Any attention this post gets will be appreciated.