To send the e-mails by the auto-server is necessary to verify before the following requirements:

1- Your computer must have direct access on Internet or access it by a router. If the access is made by a proxy, the Newsletter won’t work;

2- If the computer has a Firewall, disable it or configure it allows Newsletter to access internet. If there is some anti-virus installed, disable the resource that checks the e-mails that are sent, because it can cause many errors in the sending.

If the DNS that Newsletter is detecting is not working, you can test some DNS’s to send e-mails. The ideal is to use the DNS of the your Internet provider.