If you have fully adopted the GDS Secure Email policy, specifically where 'hard-fail' rules have been configured for email that originates from outside your network, you will need to make adjustments to accommodate all email that originates from ieg4.
Please note, if the required adjustments are not made it will result in email being filtered at network level, and not being delivered to either yourselves, or citizens.
At a high-level, two components need to be configured
DKIM is a method of electronically signing an outgoing email with an encryption key associated with your domain name. When the email is read by the recipient mail server, the key can be validated, and the email deemed authentic.
SPF is a method of listing approved network hosts that are permitted to send email on behalf of your domain name.
This may sound complex, but fortunately we have made the setup process very simple, using our email partner, SendGrid.
With the addition of three CNAME entries into your DNS, and a host added to your SPF record we can fully sign and deliver emails that appear to originate from one of your own email addresses, providing the best possible chance of delivery, and avoiding spam filters.
Please open a support ticket requesting the set up of *DKIM and *SPF and we will then provide you with the changes required to your DNS and SPF record.