A well known abuser of the game got your CD key (ban link). That CD key has been used all over the world. If you bought it from an online site, buy it from a reputable source instead. If you didn't, do what Injuneer said, as you likely have some nasty software on your computer. Either way, the ban won't be lifted, as there would be nothing to stop the hacker from continuing to do so once it was. Solution is to buy a new copy of the game from a reputable dealer, and scan your computer for malware if needed.