PieFed Instance Not Sending E-mails?

As the topic would suggest I've run into another problem with PieFed...I have Mailgun set up as my SMTP host for password resets and the like, the password to my knowledge is correct as I've tested the configuration out in a separate Python script and it logged into smtp.mailgun.org successfully on port 587.

Has anyone else set up Mailgun or similar external SMTP hosting that may be able to help debug the issue?