Helo command rejected

This page describes the reasons behind the following errors and what can be done to correct these problems.

HELO Errors

Helo command rejected: need fully-qualified hostname
Helo command rejected: Invalid name
Helo command rejected: Access denied

These errors all result from the incorrect configuration of the sender's mail server or computer.

The Reason

The standards that define how email is transferred between sender and recipient say:

RFC 821 - Simple Mail Transfer Protocol (SMTP) (Section 3.5)

  HELO <domain>

  In the HELO command the host sending the command identifies
  itself; the command may be interpreted as saying "Hello, I am
  <domain>".

RFC 2821 - Simple Mail Transfer Protocol (SMTP) (Section 3.6)

  The domain name given in the EHLO command MUST BE either a primary
  host name (a domain name that resolves to an A RR) or, if the host
  has no name, an address literal as described in section 4.1.1.1.

(RFC 2821 was published in April 2001 and updated the previous RFC 821)

A mail server that does not comply to these standards will be rejected. Additionally, a mail server that does comply, but claims to be a host it clearly is not, will also be rejected.

The Solution

Fortunately, the solution is simple. Two options exists:

Forward your outgoing email to your Internet Provider's mail server.
Their server will have correct setup and will also accept mail from you because you are connected to their network.
Configure your mail server or computer so it knows it's full hostname.
While the steps involved are beyond the scope of this document, your system must identify as 'system.domain.name.com' rather than simply 'system'. The name 'system.domain.name.com' should also resolve in the DNS to fully comply.

Relay Errors

Relay access denied

This error result from an attempt to use an email server you are not authorised to use.

The Reason

Email servers are configured to provide service to authorised user only. More technically, a mailer will only accept a message to a local email address or from a network it considers local. Less technically, if you are "out there on the Internet" and trying to send an email to someone else who is "out there on the Internet", what has it got to do with us?

The Solution

The solution is simple. Either:

Forward your outgoing email to your Internet Provider's mail server.
If you currently connect to '123XYZ Internet' but host your domain with us, you should be using 'mail.123xyz.net' for your outgoing (SMTP) setting. '123XYZ Internet' will have given you this detail when you connected to them. We can not help you identify this information.
Authenticate
In some situations, you may be able to have your mail programme identify itself to us in a way that would allow you to send using our mailer. Unfortunately, some ISPs will prevent this. If you are in this situation, you will only be able to use the first option.