Basic Requirements Please note the following basic requirements and specifications:
*  Have a low retry time on your SMTP server, to minimise the delay between delivery retries.
*  SMTP from your application or SMTP server directly to our SMTP servers, and not via third parties (e.g. your ISP).
*  Use SMTP authentication (from your SMTP server or from your application). Visit the SMTP auth instructions after logging in to your account).
Visit the SMTP auth instructions after logging in to your account).