Summary
If you send business emails, you have probably already encountered deliverability problems. Who hasn’t dreamed of seeing their messages land directly in inboxes and not in spam?
Fortunately, there are solutions to improve the confidence of mail servers in your mailings. One of them is the Sender Policy Framework (SPF), a protocol for email authentication and to prevent your domain from being usurped.
Why is SPF important for the security and deliverability of emails?
Imagine that someone uses your email address to send fraudulent messages. Not only can this damage your reputation, but it can also result in your domain being banned from email servers. This is exactly what SPF helps to prevent.
With SPF, you specify which servers are authorized to send emails on your behalf. This reduces the risk of your legitimate emails being flagged as spam and protects your domain against phishing and identity theft.
SPF works in conjunction with DKIM (which adds a digital signature to your emails) and DMARC (which defines a global policy to protect your domain). Together, these protocols make your mailings more reliable.
How does the SPF registration work?
SPF is based on a DNS record that acts as a white list of servers authorized to send emails for your domain.
An email or marketing campaign
is sent to a recipient from your sending domain.
The receiving server checks whether the sender's IP address is listed in the domain's SPF record.
If the IP address is authorized, the email will be delivered. Otherwise, it may be rejected or flagged as suspicious.
What does an SPF registration look like?
An SPF record is a simple line of text added to your domain’s DNS settings. Here is an example of a record:
v=spf1 include:example-mail.com include:another-server.com -all
Let’s break down this line:
- v=spf1 : indicates that it is an SPF record
- include:example-mail.com : authorizes the servers of this service (such as Gmail, MailChimp, Yahoo, etc.) to send emails on your behalf
- -all: means that servers not previously listed will be rejected
A well-thought-out configuration prevents your emails from being wrongly blocked and protects your reputation as a sender.
How can I set up SPF registration?
The SPF configuration is done directly in the DNS settings of your host (OVH, Google Domains, etc.). Here are the general steps:
Log in to your DNS management interface on your server.
Add a new TXT record.
Enter your SPF configuration.
Save the changes and wait for them to be propagated.
Test your configuration with an SPF verification tool.
Some platforms such as Google Workspace or Microsoft 365 provide ready-to-use SPF records, which greatly simplifies the process.
Common mistakes with SPF and how to avoid them
Even though SPF is a powerful tool, it can cause problems if it is configured incorrectly. Here are some common mistakes:
Too many DNS searches
SPF is limited to a maximum of 10 DNS searches. If you exceed this limit, your registration may be ignored.
Forgetting to include a sending server
If you use several services to send emails (Gmail, Outlook, Mailchimp, etc.), make sure to include their servers in your SPF record.
Syntax error
A missing space or an incorrectly placed directive can render SPF ineffective. Always check your configuration with a tool such as MXToolbox.
Why is SPF alone not enough?
SPF is a good first step, but it only protects the sender’s IP address. It does not guarantee that the content of the message has not been altered en route. This is where a DKIM and DMARC signature come in.
- DKIM adds a digital signature to your emails, guaranteeing their authenticity.
- DMARC, or Domain-based Message Authentication, Reporting and Conformance, imposes a strict policy on how SPF and DKIM must be applied.
Using these three protocols, SPF, DKIM and DMARC, allows you to avoid many deliverability problems and increase the confidence of email services in your mailings.
Regular monitoring and updating of SPF for optimal performance
Email authentication is a process that is not limited to an initial configuration. Your sending infrastructure may evolve over time. You may change service providers, add new services or modify your DNS configuration. It is therefore necessary to monitor your SPF record and adjust it accordingly if necessary.
A good way to stay in control is to consult your DMARC reports. This allows you to detect any non-compliant mailings. Also regularly test your SPF sender with tools to make sure it works and does not cause false positives that could harm your communication.
How can you check that your SPF is working properly?
Once your SPF record is in place, it is crucial to test it. Tools such as MXToolbox or Google Admin Toolbox allow you to check that everything is configured correctly.
It is also recommended that you regularly monitor your DMARC reports to identify any problems and adjust your configuration if necessary.
Protect your emails and improve their deliverability
SPF is an indispensable tool to prevent your emails from being marked as spam or used by cybercriminals. When configured correctly, it protects your domain and improves your sender reputation.
But to protect your emails, remember to also activate DKIM and DMARC. A good combination of these protocols guarantees that your emails will arrive in your recipients’ inboxes.
Want to be sure that your SPF is properly configured? MailSoar will help you optimize your email infrastructure and maximize your deliverability.
