Make sure you have a current, valid email address set in your profile and set a password so you can login without it. If you get locked out after that time, you can choose "Forgot Password" to fix it as long as a valid email is on your account.
I updated my dev Vanilla 2.4b1 install and then I see that Vanilla talk about recaptcha.net
But recpatcha.net is now down !
This must be http://google.com/recaptcha now ^^
I changed it in french but need to be changed on all locales.