I transferred my forum over to a new hosting provider, I downloaded a clean version of xenforo (probably a more recent release than what I had on my old server) and uploaded it, modified the config.php file, then I just copied all the database tables from my previous server to the new one. Now when I go on the forum it just says: "The board is currently being upgraded. Please check back later." I can't even log in. How do I diagnose what the problem is? The problem may be that the database structure does not match the recent version 1.5.5. How can I fix that?