DNS Health Checks: Is Your Email Setup Actually Correct?

What Is a DNS Health Check?

Your domain is like the business’s front sign, but online, the directory that tells the internet where to find you is called DNS. When that directory has wrong information, emails get lost, websites go down, and customers can’t reach you. A DNS health check is a quick, automated scan that looks at your domain’s DNS records—the digital instructions that say “send email here” or “allow this service to send on our behalf”—and flags anything that’s misconfigured, missing, or outdated.

DNS stands for Domain Name System. Think of it as the internet’s phonebook. Instead of looking up a phone number, computers look up a domain name and get back the IP address or mail server details. Your domain’s DNS records are public; anyone can look them up. A health check simply queries those records systematically to see if they’re set up correctly, especially the ones that affect email delivery and security.

Real-World Analogy

Think of a DNS health check like a routine building safety inspection. The inspector walks through and checks that fire alarms work, exits are clear, and plumbing doesn’t leak—not because there’s a known problem today, but to prevent a disaster tomorrow. Similarly, a health check scans your domain’s records to catch small issues before they cause email failures or security gaps.

How DNS Health Checks Work

When you run a DNS health check, the tool acts like a detective. It visits your domain’s public records and asks: “Are the instructions clear? Is there a trusted sender list? Is the mailbox address correct?” For email, it checks things like who’s allowed to send mail from your domain (that’s the SPF record), whether a digital signature is in place so emails can’t be easily faked (DKIM), and what to do with impostor messages (DMARC). Then it produces a simple report: green for correct, yellow for a warning, red for a critical problem. You don’t need to understand DNS to read it—just like you don’t need to be a mechanic to know the check engine light is on.

Technical Details

Here’s what a health check inspects for email-related DNS records:

▸SPF (TXT record at the domain root) — verifies the list of IP addresses and services authorized to send email on your behalf. Common syntax: . A missing or overly permissive SPF record is a major red flag.

▸DKIM (TXT record, typically with a selector prefix like ) — contains a public key that email receivers use to validate the digital signature on your outgoing messages. A missing or invalid DKIM record means your emails lack a critical trust signal.

▸DMARC (TXT record at ) — tells receiving servers what to do when email fails SPF or DKIM checks: none (do nothing), quarantine (send to spam), or reject (block entirely). A missing DMARC leaves your domain unprotected from spoofing.

▸MX records — define where your incoming email is delivered (e.g., ). A misconfigured MX can silently drop messages.

▸A, AAAA, CNAME — while less directly about email, these affect your website and overall domain resolution, which indirectly influences sender reputation.

Why It Matters for Your Business

When DNS records are correct, your emails land in inboxes. Marketing campaigns reach customers. Sales proposals get seen. Support replies don’t vanish into a spam folder. And nobody can easily impersonate your domain to trick clients or employees.

When they’re wrong, the consequences hit where it hurts: revenue, trust, and time. Emails can be rejected without anyone knowing—your team sends confidently, but the other side sees nothing. Spammers can forge your domain and ruin your reputation, causing email providers to automatically flag even your legitimate messages. Fixing these problems after the fact often means days of back-and-forth with IT or your email provider, while customers go unanswered.

This isn’t just an IT concern. Marketing cares about deliverability rates. Sales cares about whether proposals get inboxed. Support cares about customers receiving resolution emails. And leadership should care that the company’s domain—the digital front door—isn’t leaving the side gate wide open.

Common Issues and Warning Signs

Most businesses don’t realize they have a DNS problem until something breaks. A health check surfaces the hidden gaps that are quietly eroding email performance. Here are real-world symptoms that often trace back to a misconfigured DNS record.

Common Issues

Your marketing emails suddenly have lower open rates. Cause: SPF record recently broke because your email platform changed its sending IPs, or a human error removed the required include statement.

A client says they never got your message, but you didn’t get a bounce. Cause: A missing DKIM signature can cause silent rejection or spam placement because the receiving server can’t verify the email’s origin.

Customers report phishing emails that look exactly like your brand. Cause: No DMARC policy (or set to ) means anyone can send mail that pretends to be from your domain, and inboxes have no instructions to block it.

You recently switched email providers and now outgoing emails are entirely blocked. Cause: Your old SPF record still only authorizes the previous provider; the new one isn’t listed.

Your TechSpy scan shows red flags next to SPF, DKIM, or DMARC. That’s the tool telling you something is broken or missing.

How to Fix or Improve DNS Health

A health check doesn’t fix problems—it pinpoints them. The good news is that most fixes are small, one-time updates to a text record. If you have access to your domain’s DNS control panel (often where you purchased the domain or through your hosting provider), you can make these changes yourself. If you don’t, the report becomes a precise action list for whoever manages your DNS.

Don’t let small DNS misconfigurations undercut your email efforts. Run a free scan at TechSpy and see your domain’s health in under a minute. Then fix it once and move on.

If you manage your DNS:

1Log in to your DNS control panel (e.g., GoDaddy, Namecheap, Cloudflare, AWS Route53, or your web host’s dashboard).

2Find the record type the scan flagged—usually a TXT record. The report will tell you exactly which record to edit (e.g., “SPF record at @” or “DKIM record with selector google._domainkey”).

3Compare the current value with the recommended one from TechSpy. Update the record by pasting the corrected text.

4Wait up to 48 hours for the change to propagate globally (most changes take minutes, but it can take longer).

5Re-run the TechSpy scan to confirm the issue is resolved.

If someone else manages your DNS:

Forward the complete TechSpy scan report (it’s shareable by URL) and a short note: “Our email deliverability scan found these issues. Can you update our DNS records as recommended?” Send it to your IT contact, web agency, or the support team at your domain registrar.