Warning: Failed opening 'XOOPS_ROOT_PATH/class/logger.php' for inclusion (include_path='.:/usr/share/pear') in /****/html/install/class/dbmanager.php on line 26

Warning: Failed opening 'XOOPS_ROOT_PATH/class/database/databasefactory.php' for inclusion (include_path='.:/usr/share/pear') in /****/html/install/class/dbmanager.php on line 27

Warning: Failed opening 'XOOPS_ROOT_PATH/class/database/XOOPS_DB_TYPEdatabase.php' for inclusion (include_path='.:/usr/share/pear') in /****/html/install/class/dbmanager.php on line 28

Warning: Failed opening 'XOOPS_ROOT_PATH/class/database/sqlutility.php' for inclusion (include_path='.:/usr/share/pear') in /****/html/install/class/dbmanager.php on line 29

Fatal error: Undefined class name 'xoopsdatabasefactory' in /****/html/install/class/dbmanager.php on line 45

インストールする途中でこんなエラーでました。何が原因でしょうか？