550 Access denied - Invalid HELO name (See RFC2821 4.1.1.1)

The 550 Access denied - Invalid HELO name (See RFC2821 4.1.1.1) error can occur if your rDNS (reverse DNS) is not setup properly with a PTR record. What this means is your device is saying one thing but when checked in a different manner it responds with another. This is something your mail server administrator or internet service provider can assist you with.

In the case of receiving the error while using a mail account with our service, please ensure you have "My Server requires authentication" enabled and you are logging in to SMTP for outgoing email. This will bypass the check altogether.

You may also have an exception placed on your account for the remote IP by creating a support ticket with our service. 

 

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