Resolved issue

In v0.1, there’s a file called: tagUserNotifcation.php On line 88, it’s calling the option “notifyOnUserTag_emailTemplate” which does not exist by default, nor does the plugin add the option. So on line 92, I delete the first part “if($template )” so it’s shows this instead: $template = file_get_contents(dirname(__FILE__) . ‘/defaultTemplate.php’); After making that change, the plugin now works in WP 3.9.1 https://wordpress.org/plugins/tag-user-notification/ Thank you @charles .amith for this hack. This resolved the Tagged User Notification not working in recent versions of wordpress.