A lot of bloggers don’t care about WordPress blog security. For example, when someone attempt fail login on your ‘wp-login.php’. it’s displays an error message “ERROR: Invalid username or password”. That kind of information is very useful for the potential hackers. This simple trick help you to hide those messages from others.
Please editit your Theme -> ‘functions.php‘ file and paste the following code snippet.
add_filter('login_errors', create_function('$a', "return null;"));
Once done, you will no longer receive error notifications.