Looking up the code suggests it might be an authentication problem - so check your SMTP settings are correct for your mail server - that you've got the right authentication type SSL/TLS/STARTTLS, correct outgoing SMTP port number (unencrypted 25, Secure SSL 465, or Secure TLS 587) and that you've got the right (device/default) e-mail user and password.
You may also need to ensure that the primary network connection is actually connected - if it's set to ethernet and you're running on wireless only (or vice-versa), then it might not send the e-mail.
HTH
