"CD-KEY is not valid" (not the first time)

[godismyhomie]

i get the CD-KEY is not valid message right, but i reinstalled less than 2 weeks ago for the same problem!!
i havent changed account and i dont know whats causing it!
i used that EA BF2 code thing in the support folder, right...
but im sure theres something wrong... it asks for the serial code on back of instructions... so i type it in and press next, then it closes. it doesnt say anything just closes. then i run that cd key finder thing (from the sticky help thread) and it say my key is ....-.... etc etc (it has my serial number but im not typing that!!).
surely this is wrong!!! that is my SERIAL NUMBER!! (on the back of instructions) not my CD KEY!!
so now my cd key has been changd to my serial number how the hell do i find out my REAL cd key?
have i got to reinstall AGAIN!?

ALSO!!
the help thread says go to the registry editor find bf2 and type in the key... how do tyou find the key in the first place if its wrong!?

[zeleguy92]

i am getting the same problem. how did you fix this?

[R4G3DK1LLER]

same here and it only happened when i installed 1.41 patch and then it work when i reinstalled bf2 but i would love to keep the patch on there so now im bored not being ranked