Do you block any domains or email addresses?

Yes - for security there are some domains and email addresses that are blocked from sending email through our service.

We do not publish a list of these domains / email addresses.
The service is not compatible with sending from free / shared email services, you can only send from your own domain name or a domain name you have administrative access to.

If you get an error message saying 'Not allowed to send from this domain' when using our authenticated SMTP mail relay please contact us and we can investigate.

Are you having a problem sending email or looking for a reliable SMTP server?

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.

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