Are you using the latest version of Apple's Mac OSX?
Please see our Mavericks 10.9 Mac Mail SMTP server setup guide here.
If you have any questions about the service please contact us.
AuthSMTP is the outgoing SMTP email service for your e-commerce website, mailing list or email program.
It works on most current computers or devices and solves many of the common problems with sending email such as relaying denied errors or blacklisting issues.
With instant setup, a money back guarantee and very low cost starter accounts you can test and start sending email in minutes with no risk.