Genelde bu hatanın çözümü şöyledir;

/*
WordPress Force Upgrade Script
Copyright (C) 2006 Mark Jaquith

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/

function txfx_log($text) {
echo $text . '
';
}

switch ($_GET['step']) :
case "1":
require('wp-config.php');
txfx_log('WordPress loaded...');
require('wp-admin/upgrade-functions.php');
txfx_log('Upgrade functions loaded...');
wp_cache_flush();
txfx_log('Object cache flushed...');
make_db_current();
txfx_log('Database made current...');
upgrade_160();
txfx_log('Data upgraded...');
$wp_rewrite->flush_rules();
txfx_log('Rewrite rules flushed...');
wp_cache_flush();
txfx_log('Object cache flushed...');
txfx_log('
');
txfx_log('Hopefully that did it! DELETE THIS FILE FROM YOUR SERVER NOW!');
txfx_log('And then, try to access your /wp-admin/');
break;
default :
txfx_log('This script will attempt to upgrade your database. It is intended for users of WordPress 1.5 or later.');
txfx_log('You should delete this script from your server after you are done using it!');
txfx_log('
');
txfx_log('Click here to attempt the upgrade');
break;
endswitch;
?>



Yukarıda verilen kodları force-upgrade.php (uzantının .php olmasına dikkat et, php.txt olursa işe yaramaz ) adlı bir dosyaya kaydet.

Ardından dosyayı ftpden wp-config.php nin olduğu dizine at

Daha sonra tarayıcı adres satırına http://www.adresin.com/force-upgrade.php yaz. force-upgrade.php isimli dosyamızı çalıştır.

Açılan sayfadan Upgrade DataBase Tables tıkla ve databaseyi güncelle. Sonra force-upgrade.php isimli dosyayı az önce yüklemiş olduğun dizinden (wp-config.php nin olduğu yerden) sil..

Sonra http://www.adresin.com/wp-admin/ yazarak giriş yap.