Gravatar always shows default image

I worked out I needed to add quotes around the parameter.

echo get_avatar(get_the_author_meta('user_email'), '70', "'" . get_bloginfo('template_directory')."/images/default.png'");

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)