Not receiving external email from workflow

[Julie_Brown]

I am creating an HR Lifecyle, and I created a Applicant Unity Form and I have Ad Hoc task called Dismiss, when the ad hoc task is selected it pulls the email address from the Unity Form into a Property, then the Property is copied to a keyword (HR-Home Email). That HR-Home Email keyword is what is selected in the Notification so when the Dismiss Ad Hoc Task is selected it will send a notification email to the applicant. The HR-Home Email keyword is set to Alphanumeric. 

The diagnostic console isn't giving me any errors, and the distribution service is running.

I can see in the diagnostic console where the email address is copied to the HR-Home Email keyword, but there is no error or sent successfully. 

Not sure what I am missing?

I can get this to work if I send to my company email address internally. 

And I even checked Archive Notifications, I go to that DocType and I can see the notification with the correct email address.

Any direction is greatly appreciated

Thanks

OnBase17

[Julie_Brown · Accepted solution]

It turn out it was our email security software stopping the email notifications.