Warning: require(/usr/www/users/castubtxbw/wp-includes/update.php): Failed to open stream: No such file or directory in /usr/www/users/castubtxbw/wp-settings.php on line 229

Fatal error: Uncaught Error: Failed opening required '/usr/www/users/castubtxbw/wp-includes/update.php' (include_path='.:/usr/share/php') in /usr/www/users/castubtxbw/wp-settings.php:229
Stack trace:
#0 /usr/www/users/castubtxbw/wp-config.php(34): require_once()
#1 /usr/www/users/castubtxbw/wp-load.php(50): require_once('/usr/www/users/...')
#2 /usr/www/users/castubtxbw/wp-blog-header.php(13): require_once('/usr/www/users/...')
#3 /usr/www/users/castubtxbw/index.php(5): require('/usr/www/users/...')
#4 {main}
  thrown in /usr/www/users/castubtxbw/wp-settings.php on line 229

Fatal error: Uncaught Error: Call to undefined function create_function() in /usr/www/users/castubtxbw/wp-includes/plugin.php:484
Stack trace:
#0 /usr/www/users/castubtxbw/wp-includes/l10n.php(858): do_action('unload_textdoma...', 'default', false)
#1 /usr/www/users/castubtxbw/wp-includes/l10n.php(898): unload_textdomain('default')
#2 /usr/www/users/castubtxbw/wp-includes/class-wp-fatal-error-handler.php(47): load_default_textdomain()
#3 [internal function]: WP_Fatal_Error_Handler->handle()
#4 {main}
  thrown in /usr/www/users/castubtxbw/wp-includes/plugin.php on line 484