CD Key Invalid !!!!!!HELP!!!!!!

[VisualaidNeeded]

Why when i try to enter any online game it comes up with cd key invalid and i enter my cd key it goes away and then it comes up again when i try to get into it again. and again ideas anyone???????

 

[PiccoRin]

someone have u´r cd-key too.
when he is playing, u couldn´t connect everywhere!!

so 1 cd-key per gamer!!