I would advice to copy over libraries
folder form the 3.4 installation.
Then try to access /index.php?option=com_installer&view=discover
and click on "Find". It should find all not installed components during update. Then check them and click "Install".
Also you can try to create postinstall_messages
table manually in the DB.
CREATE TABLE IF NOT EXISTS `nwo4j_postinstall_messages` (
`postinstall_message_id` bigint(20) unsigned NOT NULL AUTO_INCREMENT,
`extension_id` bigint(20) NOT NULL DEFAULT 700 COMMENT 'FK to #__extensions',
`title_key` varchar(255) NOT NULL DEFAULT '' COMMENT 'Lang key for the title',
`description_key` varchar(255) NOT NULL DEFAULT '' COMMENT 'Lang key for description',
`action_key` varchar(255) NOT NULL DEFAULT '',
`language_extension` varchar(255) NOT NULL DEFAULT 'com_postinstall' COMMENT 'Extension holding lang keys',
`language_client_id` tinyint(3) NOT NULL DEFAULT '1',
`type` varchar(10) NOT NULL DEFAULT 'link' COMMENT 'Message type - message, link, action',
`action_file` varchar(255) DEFAULT '' COMMENT 'RAD URI to the PHP file containing action method',
`action` varchar(255) DEFAULT '' COMMENT 'Action method name or URL',
`condition_file` varchar(255) DEFAULT NULL COMMENT 'RAD URI to file holding display condition method',
`condition_method` varchar(255) DEFAULT NULL COMMENT 'Display condition method, must return boolean',
`version_introduced` varchar(50) NOT NULL DEFAULT '3.2.0' COMMENT 'Version when this message was introduced',
`enabled` tinyint(3) NOT NULL DEFAULT 1,
PRIMARY KEY (`postinstall_message_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
INSERT INTO `nwo4j_postinstall_messages` (`extension_id`, `title_key`, `description_key`, `action_key`, `language_extension`, `language_client_id`, `type`, `action_file`, `action`, `condition_file`, `condition_method`, `version_introduced`, `enabled`) VALUES
(700, 'PLG_TWOFACTORAUTH_TOTP_POSTINSTALL_TITLE', 'PLG_TWOFACTORAUTH_TOTP_POSTINSTALL_BODY', 'PLG_TWOFACTORAUTH_TOTP_POSTINSTALL_ACTION', 'plg_twofactorauth_totp', 1, 'action', 'site://plugins/twofactorauth/totp/postinstall/actions.php', 'twofactorauth_postinstall_action', 'site://plugins/twofactorauth/totp/postinstall/actions.php', 'twofactorauth_postinstall_condition', '3.2.0', 1),
(700, 'COM_CPANEL_MSG_EACCELERATOR_TITLE', 'COM_CPANEL_MSG_EACCELERATOR_BODY', 'COM_CPANEL_MSG_EACCELERATOR_BUTTON', 'com_cpanel', 1, 'action', 'admin://components/com_admin/postinstall/eaccelerator.php', 'admin_postinstall_eaccelerator_action', 'admin://components/com_admin/postinstall/eaccelerator.php', 'admin_postinstall_eaccelerator_condition', '3.2.0', 1),
(700, 'COM_CPANEL_WELCOME_BEGINNERS_TITLE', 'COM_CPANEL_WELCOME_BEGINNERS_MESSAGE', '', 'com_cpanel', 1, 'message', '', '', '', '', '3.2.0', 1),
(700, 'COM_CPANEL_MSG_PHPVERSION_TITLE', 'COM_CPANEL_MSG_PHPVERSION_BODY', '', 'com_cpanel', 1, 'message', '', '', 'admin://components/com_admin/postinstall/phpversion.php', 'admin_postinstall_phpversion_condition', '3.2.2', 1),
(700, 'COM_CPANEL_MSG_ROBOTS_TITLE', 'COM_CPANEL_MSG_ROBOTS_BODY', '', 'com_cpanel', 1, 'message', '', '', '', '', '3.4.0', 1);