GLOBAL PunkBuster GUID BAN xxxxxxxx
means either that you are trying to play on legit servers with a non-legit key or that you got a key that is banned globally by PB even on cracked servers for e.g. cheating.
(I'm assuming you do not have a legit key)
Are you sure you are connecting to cracked servers where legit key isn't required?
Here you have some servers to test on:Serverlist
If it still says GUID BAN you have to change your Keycode
to a not banned one. Use a keygen getting a banned key from it would be like winning the lottery.
You can add my Skype if you need some more help (Untriggered)
I do not know if posting illegal stuff here is ok xD.
BTW...Google is your friend.