Create a WordPress administrator user via FTP

newadmin.php

<?php
    //Need WordPress access but only have FTP access? 
    //This snippet will let you create an administrator user, as long as you can get it onto the server in the root of the site
    //Then visit https://www.site.com/newadmin.php
    //Finally, DELETE THE SCRIPT when you have gained access.

    require_once('wp-load.php');
    $userdata = array(
        'user_login' =>  'newadmin',
        'user_email'   =>  '[email protected]',
        'user_pass'  =>  'Secretpassword!!1'
    );
    $user_id = wp_insert_user( $userdata );
    if(is_wp_error($user_id)){
        echo $user_id->get_error_message();
        die();
    }
    $user = new WP_User( $user_id );
    $user->add_role( 'administrator' );
    echo "Successfully created user {$userdata['user_login']}";