This error occurs when you try and login too many times in a row in a very short time period. Our firewall believes you are trying to hack the system and so a temporary block is placed on your IP address. The block can only be lifted automatically and it happens after ONE HOUR as long as you do not continue trying to login. Please make 100% sure that you are using the correct username and password when logging into Aurora. If you recently changed your password and have auto-login enabled, you may need to hold down SHIFT when you run Aurora and set it back to default settings so you can enter your new password.