.htacess in wp-admin?

Hi all,

I have to protect my wp-admin folder by pass. So i try to use .htacess

I tried this code but it got 404 error.

# BEGIN WordPress
    <IfModule mod_rewrite.c>
    RewriteEngine On
    RewriteBase /
    RewriteRule ^index\.php$ - [L]
    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteCond %{REQUEST_FILENAME} !-d
    RewriteRule . /index.php [L]
    </IfModule>
    # END WordPress

AuthType Basic
AuthName "Secure Area"
AuthUserFile "/home/example/.htpasswds/public_html/wp-admin/passwd"
require valid-user

I tried next code but it got a re-direct loop.

ErrorDocument 401 "Denied"
ErrorDocument 403 "Denied"

# Allow plugin access to admin-ajax.php around password protection
<Files admin-ajax.php>
Order allow,deny
Allow from all
Satisfy any
</Files>

AuthType Basic
AuthName "Secure Area"
AuthUserFile "/home/example/.htpasswds/public_html/wp-admin/passwd"
require valid-user

And i try to fix following the guide http://www.inmotionhosting.com/support/website/wordpress/prevent-unauthorized-wp-admin-wp-login-php-attempts

but it still get a re-direct loop

Plz help me.