Players who are getting "Empty CDKey" messages trying to connect to PunkBuster ET Servers may attempt a manual CDKey registration.

Press the accent key (the ^ key) to bring down the game console from any game screen and enter the following command (without quotes): "/pb_cdkeyreg".

You should see a message stating that a Registration Request was sent to the GuidAuth Master Server. After a few seconds (perhaps up to 30 seconds) you should see a message stating that the CDKey Registration was successful. After that, there should be no more messages about an Empty CDKey when trying to join a PB Server.