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If you are getting “Relaying Denied” error messages from your SMTP server when trying to use SMTP2GO as a smarthost, the following may help.

Step 1

Unix SMTP servers often try to route mail using the MX record – this will not give satisfactory results if used with SMTP2GO.
Instead enclose mail.smtp2go.com within square brackets, so that it will become like this:



Step 2

In many applications this will tell it to use the ‘A record’ instead and it should then work.

Note: If you see an error ‘550 unable to verify sender address’ when trying to send an email after setting up, this means your ‘From’ email address doesn’t have a valid MX record setup yet. All emails must be sent from an email address that has an MX record at its domain name.

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