Mail providers like Gmail and Outlook check that your domain is set up to prove your emails are real. Missing or incorrect SPF, DKIM, and DMARC records are the most common reason business email goes to spam. Fixing those DNS records solves most deliverability problems.
Common causes
Missing SPF, DKIM, or DMARC
Without these records, receiving servers can't verify your email is legitimate.
Other services sending as your domain
Website forms, invoicing tools, and marketing platforms must be included in SPF and DKIM.
Spam-like content
Link-heavy messages, all-image emails, and certain phrases trigger filters.
Sending reputation
A compromised account sending spam can damage your domain's reputation.
How to fix it, step by step
- 1
Check your SPF record
Make sure your domain has one SPF record listing every service that sends email for you.
- 2
Turn on DKIM
Enable DKIM signing in Microsoft 365 (or your email provider) and publish the DNS records.
- 3
Add a DMARC record
Start with a monitoring policy and tighten it once SPF and DKIM pass consistently.
- 4
Check other senders
Set up authentication for your website, CRM, and invoicing tools too.
- 5
Test a message
Send to a Gmail account and use "Show original" to confirm SPF, DKIM, and DMARC pass.
When to call a technician
DNS changes can stop email entirely if done wrong. We audit your domain, set up SPF, DKIM, and DMARC correctly, and make sure your website forms and other tools are included.
On-site support across Orange County · see our IT support, managed IT, Microsoft 365 support and cybersecurity services.
Frequently asked questions
What are SPF, DKIM, and DMARC?
They're DNS records that prove email from your domain is genuine. SPF lists allowed senders, DKIM signs messages, and DMARC tells receivers what to do with failures.
Why did our emails start going to spam recently?
Gmail and Yahoo tightened their requirements for authenticated email, and domains without proper setup are filtered more often.
Can our website contact form affect email delivery?
Yes. If the form sends as your domain without authentication, those messages can fail and hurt your domain's reputation.