Database problem after Joomla upgrade: 1.5.x to 1.5.26

I'm having database problem after Joomla 1.5 upgrade to 1.5.26. _components and _plugins were said to be missing, and on the login page I got this error: Error Loading ModulesUnknown column 'control' in 'field list' SQL=SELECT id, title, module, position, content, showtitle, control, params FROM xgrda_modules AS m LEFT JOIN xgrda_modules_menu AS mm ON [login to view URL] = [login to view URL] WHERE [login to view URL] = 1 AND [login to view URL] <= 0 AND m.client_id = 1 ORDER BY position, ordering Top page shows error 404. Thanks for reading.