Medieval2:total war~i av just set up an account at gamespy but when i log in it wont let me?

it says "failure to logon-cd key invalid"or something like that, why does it happen and how do i get round it

This is a problem many people face, the CDKEYS printed on the manual are usually confusing and have zeros looking like O's, There are no O's just zeros in the key. To fix this problem, completely exit out of the game and go to Start->Run then type in regedit, after you type in reg edit, navigate to HKEY_LOCAL_MACHINE/SOFTWARE/SEGA/Medieva... II Total War double click on the entry that says CD-KEY and change the O's to zeros. Also go by these rules

*Don't type spaces

*Do type the "-"s

*Don't use "o"s use zero's

*Type everything (except for the numbers obviously) in capital letters