Process Bulk CiviMail responses for a variety of SMTP Services including:
Drupal Ex: http://{yourDomain}/civicrm/airmail/settings
Wordpress Ex: http://{yourDomain}/wp-admin/admin.php?page=CiviCRM&q=civicrm%2Fairmail%2Fsettings
Enter a secret code, it does not matter what this code is should be a random string of numbers and letters. For Open/Click Processing slect "CiviMail" For External SMTP Service Select the service you are using.
Save Configuration
On save the post URL should display below in a green box it will look something like this:
Wordpress Ex: http://{yourDomain}/civicrm?page=CiviCRM&q=civicrm/airmail/webhook&reset=1&secretcode={secretCode}