Wp redirect – reset password

(Revised answer)

The problem with your code is that the password reset link/URL is missing the proper password reset key and user login slug — the $key (password reset key) and $user_login (user login slug) as you can see below, are both missing (i.e. not defined anywhere in your code):

network_site_url("wp-login.php?action=rp&key=$key&login=" . rawurlencode($user_login), 'login')

So to fix the problem:

1. Replace this:

   if ( $post->post_status == 'publish' ) {
     wp_redirect("" . network_site_url("wp-login.php?action=rp&key=$key&login=" . rawurlencode($user_login), 'login') . "");
     exit();
   }
   

   with this:

   if ( $post->post_status == 'publish' ) {
     if ( ! $user = get_user_by( 'email', $_GET['email'] ) ) return;
     $key = get_password_reset_key( $user );
     wp_redirect("" . network_site_url("wp-login.php?action=rp&key=$key&login=" . rawurlencode($user->user_login), 'login') . "");
     exit();
   }
   

2. Replace this:

   // work finished, view the post
   wp_redirect("" . network_site_url("wp-login.php?action=rp&key=$key&login=" . rawurlencode($user_login), 'login') . "");
   

   with this:

   // work finished, view the post
   $key = get_password_reset_key( $author );
   wp_redirect("" . network_site_url("wp-login.php?action=rp&key=$key&login=" . rawurlencode($author->user_login), 'login') . "");
   

And note that the init hook doesn’t pass any parameters to the callback function (which in your case is approve_post()), so your code should be just:

add_action( 'init', 'approve_post' );

So the approve_post() function should be defined without any parameters:

function approve_post() // like this
function approve_post($user, $notify) // not this

And hooking to the init action only is enough; so this is not necessary:

add_action('edit_user_created_user', 'approve_post', 10, 2 );

This is also not necessary — at the end of the function (before the closing }), you don’t need to return anything:

return $notify; // just remove this