How to Fix a Missing DMARC Record (15-Minute Guide for Omaha Business Owners)

Here's the single biggest security gap we find on Omaha small business domains: missing or unenforced DMARC.

About 70% of Omaha businesses we scan have weak or missing DMARC. That means attackers can send phishing emails from you@yourcompany.com to your customers, vendors, and employees — and Gmail and Outlook will deliver them to the inbox, no warnings, no spam folder. This is how virtually all wire-fraud and CEO-impersonation scams start.

Good news: fixing DMARC takes about 15 minutes if you have access to your domain's DNS settings. Here's the plain-English version.

What Is DMARC, Really?

DMARC stands for Domain-based Message Authentication, Reporting & Conformance. Strip the jargon, and it's just a single line of text you publish in your domain's DNS that tells the entire internet's email servers:

“If you receive an email pretending to be from my domain that didn't actually come from my email server, here's what to do with it.”

Without DMARC, every email server in the world has to guess. Most guess wrong, and the spoofed email gets delivered.

The Three DMARC Policies (Easy Version)

The mistake we see all the time: businesses set p=none and never move past it. p=none protects you from absolutely nothing — it's just monitoring. You have to graduate to p=quarantine and then p=reject to actually stop spoofing.

Prerequisite: You Need SPF First

DMARC depends on SPF (Sender Policy Framework). If you don't have an SPF record, fix that first. Add a TXT record at the root of your domain (the @ hostname):

v=spf1 include:_spf.google.com -all

(That's for Google Workspace. For Microsoft 365, use include:spf.protection.outlook.com. For other senders like Mailchimp, SendGrid, or Constant Contact, add their include: entries too.)

End it with -all, not ~all. The tilde version is a soft-fail that attackers can still exploit.

The 15-Minute DMARC Fix (Step by Step)

Step 1: Log in to your DNS provider (2 min)

This is wherever your domain is registered: GoDaddy, Namecheap, Cloudflare, Google Domains, etc. Find the DNS management page. You're going to add one new TXT record.

Step 2: Add the starter DMARC record (3 min)

Create a new TXT record with these settings:

• Hostname / Name: _dmarc (just that — your DNS provider will append your domain automatically)
• Type: TXT
• Value: v=DMARC1; p=none; rua=mailto:dmarc@yourcompany.com; ruf=mailto:dmarc@yourcompany.com; fo=1
• TTL: 3600 (or default)

Replace dmarc@yourcompany.com with a real email address you actually check (or set up a free dmarcian account to get human-readable reports). You'll start receiving daily DMARC aggregate reports within 24–48 hours.

Step 3: Wait one to two weeks and review reports (passive)

The reports tell you which servers are sending email "as" your domain. You're looking for two things:

• Legitimate senders — your email service (M365/Google), your CRM (HubSpot/Mailchimp), your accounting tool, your help desk software. All of these need to be in your SPF record.
• Illegitimate senders — random servers in countries you don't operate in. These are spoofers.

If a legitimate sender is failing DMARC, fix your SPF record before tightening DMARC further. Otherwise you'll block your own emails.

Step 4: Move to quarantine (5 min)

Once your reports show all legitimate senders passing, edit your DMARC record:

v=DMARC1; p=quarantine; pct=100; rua=mailto:dmarc@yourcompany.com; ruf=mailto:dmarc@yourcompany.com; fo=1

Now any spoofed email gets dumped in the recipient's spam folder. Wait another week and verify nothing legitimate is broken.

Step 5: Move to reject (5 min)

Final step. Edit the record one more time:

v=DMARC1; p=reject; pct=100; rua=mailto:dmarc@yourcompany.com; ruf=mailto:dmarc@yourcompany.com; fo=1

Now spoofed emails are rejected outright — they never reach your customer's inbox. Done.

How to Verify It's Working

Run our free DMARC checker or our full Hacker View scan. You should see DMARC status: Pass, with policy p=reject. The exposure score on the full scan should drop by 22 points.

Common Mistakes to Avoid

• Stopping at p=none. This is the most common mistake. p=none is monitoring, not protection. Move to p=quarantine within 2 weeks.
• Forgetting third-party senders. Mailchimp, HubSpot, Constant Contact, SendGrid, Postmark, your help desk, your CRM — all need include: entries in your SPF record or DKIM aligned.
• Using ~all in SPF. The soft-fail allows spoofers to slip through. Always use -all.
• Setting up DMARC without SPF. DMARC needs SPF or DKIM (or both) to work. Most small businesses do SPF first because it's simpler.
• Not monitoring reports. Set up dmarcian or use a service like Valimail or EasyDMARC. The free tiers are plenty for an Omaha small business.

What You Just Prevented

With p=reject in place, the following attacks become impossible against your customers:

• CEO impersonation ("Hi, this is the CEO, can you wire $40,000 to this account before lunch?")
• Vendor invoice fraud (fake invoice that looks like it came from your accounting team)
• HR phishing (fake "please update your direct deposit info" emails to employees)
• Customer phishing campaigns that damage your brand and trigger lawsuits

Verizon's 2025 Data Breach Investigations Report puts Business Email Compromise (BEC) losses at over $2.7 billion globally last year. The vast majority of those attacks would have been blocked by p=reject on the spoofed domain.

Help Is Available

If you'd rather not deal with DNS records yourself, our team in Omaha will roll out SPF, DKIM, and DMARC across your domain in 30–60 minutes — usually as part of a broader Microsoft 365 hardening or cybersecurity engagement.

👉 Cybersecurity services in Omaha → or call 402-650-8407.

The 30-Second Verification

Already done? Verify your domain's DMARC posture right now: Run a free Hacker View scan →. You'll see your DMARC status, your exposure score, and a comparison against other Omaha businesses on the Exposure Leaderboard.