Fatal error: Uncaught mysqli_sql_exception: mysqlnd cannot connect to MySQL 4.1+ using the old insecure authentication. Please use an administration tool to reset your password with the command SET PASSWORD = PASSWORD('your_existing_password'). This will store a new, and more secure, hash value in mysql.user. If this user is used in other scripts executed by PHP 5.2 or earlier you might need to remove the old-passwords flag from your my.cnf file in /home/matiere4u/cotoha.jp/public_html/wp/wp-includes/wp-db.php:1498
Stack trace:
#0 /home/matiere4u/cotoha.jp/public_html/wp/wp-includes/wp-db.php(1498): mysqli_real_connect(Object(mysqli), 'mysql16.xserver...', 'matiere4u_cthwp', '1Kg8as3i', NULL, NULL, NULL, 0)
#1 /home/matiere4u/cotoha.jp/public_html/wp/wp-includes/wp-db.php(649): wpdb->db_connect()
#2 /home/matiere4u/cotoha.jp/public_html/wp/wp-includes/load.php(352): wpdb->__construct('matiere4u_cthwp', '1Kg8as3i', 'matiere4u_cthwp', 'mysql16.xserver...')
#3 /home/matiere4u/cotoha.jp/public_html/wp/wp-settings.php(79): require_wp_db()
#4 /home/matiere4u/cotoha.jp/public_html/wp/wp-config.php(71): require_once('/home/matiere4u...')
#5 /home/matiere4u/cotoha.jp/public_html/wp/wp-load.php(29): require_once('/home/matiere4u...')
#6 /home/matiere4u/cotoha.jp/public_html/wp/wp-blog-header.php(12): require_once('/home/matiere4u...')
#7 /home/matiere4u/cotoha.jp/public_html/index.php(17): require('/home/matiere4u...')
#8 {main}
thrown in /home/matiere4u/cotoha.jp/public_html/wp/wp-includes/wp-db.php on line 1498