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.
Hello. I downloaded Czech locale, I extracted it in /locales folder, enabled it in Addons -> Locales and set it as default, but site is still in English. What I'm doing wrong? I'm using Vanilla 2.1.10.