"D" key problem...

Okay, this is new account, because I forgot my old ones password and name, and I didn't play Crossfire for long..... The reason I quit playing, was because I couldn't use the D key, it has no reaction when moving whatsoever... It only reacts when you try and change settings, or type in chat... And it is pretty hard playing with "F" key. I didn't try changing keyboard, so if I don't fix this one, or better say this problem, I shall change the keyboard. And if the problem doesn't solve even than, I'll stop playing completely. Oh and the "D" key, /does/ work in other games... Sooo, if anyone can help me solving this, please help~

Thank you, XxDDevilxX