Blog pages will no longer display after upgrade

After upgrading today to the current version, I get the following error message when clicking on links to display an individual blog page:

Warning: require_once(/home/www/html/subs/travel/en/components/com_easyblog/helpers/helper.php): failed to open stream: No such file or directory in /home/www/html/subs/travel/en/plugins/opengraph/easyblog/easyblog.php on line 41

Fatal error: require_once(): Failed opening required '/home/www/html/subs/travel/en/components/com_easyblog/helpers/helper.php' (include_path='.:/usr/share/pear:/usr/share/php') in /home/www/html/subs/travel/en/plugins/opengraph/easyblog/easyblog.php on line 41

Any suggestions to resolve this problem?

Thank you. -- Rik

PS: I don't notice any other problems after the upgrade.