When an SPF validation error occurs, recipients’ mail servers stop accepting emails from a particular source sending emails using your domain. This can cause email delivery and SPF authentication issues if it starts to happen to genuine messages and senders as well. SPF records include all IP addresses and email servers that are used by people who are officially permitted to send emails from your business domain. 

Any sender’s IP address or email server outside of the list is identified as fraudulent. In this situation, the domain owner receives an invalid SPF record delivery status result saying-  “Error 550 – Message refused due to a failed SPF check.”

To avoid an SPF validation error in Office 365 Exchange and other mailbox operators, you need to bear in mind that your SPF TXT record at your domain registrar has no misconfigurations. There are two types of SPF errors- SPF permerror and SPF temperror.

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Let’s answer the question that brought you here- How do I fix SPF validation error, but before that, we’ll check out some common reasons and preventive measures.

Common Reasons Causing an SPF Validation Error

SPF, DKIM, and DMARC work in compliance with each other and support the servers of recipients to identify genuine and fraudulent emails sent from a specific domain. This results in minimizing the chances of users opening spam messages and becoming victims of ransomware, malware, business email compromise (BEC), phishing, identity theft, and other types of cyberattacks. 

Bear in mind that hackers crack ways to bypass spam filters; thus, as a company host, implying SPF, DKIM, and DMARC is crucial to get rid of the email security and delivery problem.

The SPF email authentication protocol functions properly if no SPF errors exist in the TXT record. Some common reasons causing a processing failure are-

  • Spam filters or message scanners fail to parse information from your domain’s SPF record.
  • It can take up to 72 hours for DNS to render a newly updated SPF record. So, an SPF validation issue can occur if it isn’t rendered.
  • You didn’t update the addition of a new in-house or third-party IP address or mail server in the SPF record, but they are being used to send emails.
  • You are unable to modify your domain’s MX record or be a user of third-party sending tools.
  • The DNS server couldn’t resolve the domain name in the DNS.
  • There are multiple SPF records for one domain. In such cases, all of them get invalid.
  • You have exceeded the limit for DNS lookups. Reach out to AutoSPF to seek support on this problem. 
  • More than 2 void lookups are spotted by an SPF checking tool for your SPF record.
  • Some syntax errors popped up during an SPF authentication check. SPF syntax is categorized into three types- Mechanisms, Qualifiers, and Modifiers. In a way, understanding and using a mechanism can be tricky for organizations and may lead to an SPF mistake.

Best Practices to Prevent SPF Validation Errors for Your Domains

Prevention is better than cure, right? So, by following these best practices, you can ward off SPF validation errors that could otherwise impede email delivery and expose your domain to phishing and spoofing attacks.

Keep your SPF records updated and always make changes whenever an IP address is included or removed from the list. If a domain is not used for sending messages anymore, then simply disable the SPF TXT record corresponding to it. This will shelter it from the evil eyes of threat actors who are always on the lookout for unprotected domain names.

If you have moved on to a different email provider (for example, from Outlook to Gmail), then Google will fail to match the sender address with any published SPF records, causing SPF validation errors. So, if your email resources have undergone anything like this, then update your SPF DNS record at the earliest to avoid a number of issues.

Another key point is to choose a reliable and reputed DNS hosting provider with good web hosting options. Otherwise, your SPF record may not always be accessible by receiver servers due to this reason.

How do I Fix SPF Validation Error- Let’s Find an Answer to This

Domain owners can avoid an SPF validation failure by taking care of the following steps-

  • Add only valid and active senders’ IP addresses or mail servers.
  • Ensuring there are no syntax problems or misconfigurations in SPF DNS records.
  • The domain mentioned in the ‘from’ field of the email header is right.
  • Both domain and mail records are linked to the accurate source SMTP server.

What is an SPF Failure?

An SPF failure means that the particular sender’s IP address isn’t listed in the SPF record of that domain, which means it isn’t officially allowed to send emails on behalf of the organization. There are two major types of SPF failures; softfail (indicated by ~all tag) and fail (indicated by a -all tag). As per SPF softfail, messages from unauthorized senders will be marked as spam. In case of an SPF fail, recipients’ mailboxes reject their entry. 

It’s highly discouraged to use the +all tag (all pass tag) as it allows anyone and everyone to send emails using your domain. So, if a malicious actor sends fraudulent content to your client, customer, or prospect, their recipient server will place it in the primary inbox. This can severely hamper your company’s reputation.