Is there a way to display content from a post meta box in the sidebar?

Well, you could access the $post variable with global $post and then access it’s meta values with get_post_meta($post->ID) or something close to that. If you just want that to be accessed when you are viewing a single post, you can use

if(is_singular('my_custom_post_type'))
//do your stuff

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