Steps to Correct Email Bounce Backs / Suspicious Flag (SPF and TXT Entry)

Microsoft recently made some changes to how they handle email security which has affected communications sent through the Atlas Communicator. Areas affected include the mass communicator and emails sent from forms on the site. There are several steps that need to be taken to correct this issue including:

1. Update the SPF record on your DNS

An SPF record is used to tell a receiving mail server that the email being sent out by the Atlas relay server isn’t spam. If you add the following records to your DNS it should eliminate most of the bounce backs, particularly in the mass communicator.

If you use Microsoft Outlook Online* as your email provider add the following as BOTH an SPF and TXT record:

v=spf1 -all

*How do I tell if I use Microsoft Outlook Online? The easiest answer is to ask your IT person. If that isn’t possible then you can go to and type your domain into the Domain Name: search field and hit MX Lookup. This will bring up information about your domain including the Hostname. If the Hostname includes at any point then you need to use the above record.

Everyone else who doesn’t use Microsoft Outlook Online needs to add the following as BOTH an SPF and TXT record:

v=spf1 -all

Please note that these need to be added as both a TXT and SPF record. It’s come to our attention that not all domain registrars support SPF records. To spare a long and technical explanation, as part of the transition to the SPF standard old email servers would accept TXT records made to look like SPF records that said “Hey! This email isn’t spam!” Some newer servers, however, have moved to only supporting the newer SPF records and so there is the potential for bouncing emails if you only have a TXT record in place.

Unfortunately there is no good solution for this at this time. You can switch to a domain registrar who does support SPF records or get in touch with your registrar and let them know this is a change that has been in the works for 8 years and you would like them to support it. Not having an actual SPF record in place means there is the potential for newer email servers to bounce mail back moving forward, but at this time the majority of mail servers will still accept a TXT record as well.

2. DNS failure notifications after you’ve put your TXT and SPF record in place

Your first check should be to see if your SPF record entry is valid, you can test your domain at the following location: 

Some clients are still getting a small number of bounce notifications after they’ve put their TXT and SPF record in place. These emails typically include notification that the email bounced because of some failure on the receiving DNS. These are the result of an issue on the receiving end and there isn’t anything that we can do about a receiving server bouncing email back.

We encourage you to contact clients whose domains are bouncing those emails back and see if they can whitelist communications both from your domain and from the Atlas relay server. It’s possible that the security change is affecting them as well and they don’t realize it.

To reiterate: If you are getting email bounce backs after adding TXT and SPF records then it is likely an issue with the receiving domain and that member should be contacted so that their IT can double check their settings and whitelist your organization.

3. Microsoft Outlook Online users

Microsoft Outlook Online users are experiencing an additional issue where if you try to email yourself a copy of an email being sent in the Mass Communicator the delivery fails. Microsoft is not allowing that email to be sent back for some reason, and the bounce back notification you receive is our email server letting you know Microsoft Outlook has rejected the email.

We are unable to control Microsoft rejecting client emails and are encouraging clients experiencing this issue to contact Microsoft directly about your account to work out a solution to this problem. They should have a recommendation for a best practice and how to proceed.

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