If you’re third party email providers, You must do the following things.

  1. Signup the service . You can signup into Elastic Email / Mandrill.
  2. Obtain your records and update in your DNS manager.
  3. Verify your domain.
  4. Obtain the SMTP details and add them in Admin – Settings – Email Settings.

Note that, If your domain is not verified, the SMTP details won’t work.