What we check
We validate SPF syntax and detect common errors
We validate SPF record syntax and detect common errors like typos, invalid mechanisms, duplicate includes, or malformed directives. A single syntax error causes complete SPF validation failure, making all your emails fail authentication checks and harming sender reputation.
Security Impact
Why SPF syntax errors are critical
One typo breaks everything
A single character typo in your SPF record causes complete authentication failure. All emails—even legitimate ones from authorized servers—fail SPF validation.
Immediate deliverability damage
When SPF breaks, receiving servers reject or spam your emails. This causes immediate, severe deliverability issues affecting your entire email program.
Errors are easy to make
SPF syntax is complex. Common mistakes include extra spaces, wrong mechanism order, missing colons, or duplicate entries. These are easy to introduce and hard to spot.
Silent failures
DNS accepts invalid SPF records without error. You won't know SPF is broken until emails start bouncing or landing in spam.
Implementation
How to fix SPF record errors
With Httpeace
Httpeace automatically validates SPF syntax and detects errors:
- Add your domain to Httpeace
- We check SPF syntax automatically every day
- Get instant alerts when syntax errors are detected
- See specific error details and fix instructions in your dashboard
Without Httpeace
Manual SPF validation requires understanding complex syntax rules:
# Check SPF record dig TXT yourdomain.com | grep spf # Online validators # Visit: https://www.kitterman.com/spf/validate.html # Visit: https://mxtoolbox.com/spf.aspx # Send test emails # Check authentication results in headers
You'll need to:
- Learn SPF syntax rules (always starts with v=spf1)
- Check for multiple SPF records (only ONE allowed per domain)
- Validate mechanism syntax (include:, ip4:, ip6:, a:, mx:)
- Ensure proper spacing between mechanisms (single spaces only)
- Verify colons are present after mechanisms (include:, not include)
- Check for typos in domain names within include: statements
- Validate qualifier syntax (+, -, ~, ?) if used
- Ensure record ends with all qualifier (~all or -all)
- Test with online SPF validators before publishing
- Wait 24-48 hours for DNS propagation
- Send test emails and verify SPF passes
- Check email headers for authentication results
- Monitor for accidental syntax changes during updates
- Keep backup of working SPF record before making changes
- Test in staging subdomain before updating production
SPF syntax errors are extremely common and cause immediate complete authentication failure. A single typo, extra space, or duplicate record breaks SPF for all emails, sending everything to spam.
FAQ
Frequently asked questions
What happens if my SPF record has a syntax error?
Any syntax error causes the entire SPF record to fail validation. This means ALL your emails—even legitimate ones from authorized servers—fail SPF authentication, causing them to be rejected or marked as spam.
Why do I have multiple SPF records?
Multiple SPF records usually happen when adding a new email service without removing the old record, or when different team members manage DNS. Remember: only ONE SPF record is allowed. Combine all email services into a single record using multiple include: statements.
How do I combine multiple email providers into one SPF record?
Use multiple include: statements in a single SPF record. For example: "v=spf1 include:_spf.google.com include:spf.mailgun.org include:sendgrid.net ~all". Watch out for the 10 DNS lookup limit.
Can I test SPF changes without breaking production email?
Yes! Create a test subdomain (like test.yourdomain.com) and test your SPF record there first. Send test emails and verify SPF passes before updating your main domain's SPF record.
How does Httpeace check for SPF errors?
We parse your SPF record daily and validate syntax according to RFC 7208. We check for common errors like multiple records, invalid mechanisms, typos, and formatting issues. We alert you immediately if we detect any errors.
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