Same Problem: "Your Account is not activated, yet. An activation mail has been sent to your email address. Please follow the activation link provided in that mail to activate your account."
My login data work for the forum, but not for the game. My email is already activated and I also found the activation mail from month ago, saying my account is already activated clicking the verification again.
Tryed not using TAB, changed my email and password, restarted launcher several times, nothing works for me.
EDIT: Just try several times, at some point it worked for me, THERE IS NO ISSUE WITH YOUR ACCOUNT GUYS!