Same error here.
Fatal error: Call to undefined method WP_Error::get_items() in plugins/better-wp-security/lib/bit51/bit51.php on line 353
I had a similar experience yesterday and tracked it down to the database table prefix being changed on the database, but not in the wp-config.php file. It remained as “wp_” – which broke my site temporarily. The solution: Log in to your database as the admin, find what the new table name prefix is, and then update your wp-config.php to match. Took about 5 minutes, and all is running smoothly again. I too, pondered doing a full restore. Luckily I sorted out what the underlying problem was…
