Your email is sending — but it's landing in spam, getting rejected, or disappearing entirely. The cause is almost always in your DNS: broken SPF, missing DKIM, or a DMARC policy that's silently killing your deliverability. We audit and fix it.
DNS email failures are sneaky. Everything looks fine on your end — the problem only shows up at the destination.
Email lands in recipient spam/junk
Your messages arrive — but they're filtered to junk because your domain fails authentication.
Rejected with "SPF fail" error
Receiving server checks your SPF record, finds a mismatch, and blocks the message outright.
DMARC quarantine or reject
Your DMARC policy is set to quarantine or reject, and legitimate email is getting caught.
Email works internally but not externally
Internal messages flow fine — it's the external world that can't receive your email reliably.
New domain or migration sending issues
After an email migration or new domain setup, DNS records often point at the wrong servers.
MX records pointing at old server
A completed migration where the MX record still routes inbound mail to the previous provider.
Modern email delivery depends on four DNS record types. All four must be correct and aligned — a single misconfiguration causes failures that are invisible to the sender.
Mail Exchange — tells the internet where to deliver inbound email
Common mistake: Most common mistake: MX still pointing at old server after switching to Microsoft 365.
Sender Policy Framework — authorizes which servers can send email as your domain
Common mistake: Most common mistake: Multiple SPF records or missing the Microsoft 365 include directive.
DomainKeys Identified Mail — cryptographic signature proving email authenticity
Common mistake: Most common mistake: DKIM enabled in Microsoft 365 but the CNAME records were never added to DNS.
Domain-based Message Authentication — policy that tells servers what to do with failures
Common mistake: Most common mistake: DMARC set to reject before SPF and DKIM are fully validated — blocks real email.
Full DNS record pull
We pull your current MX, SPF, DKIM, and DMARC records and check them against what your mail provider requires.
SPF alignment check
We verify your SPF record includes all authorized sending sources — Microsoft 365, third-party senders, and any marketing tools your business uses.
DKIM key validation
We confirm DKIM selector CNAME records are published in DNS and match the keys configured in your Microsoft 365 tenant.
DMARC policy review
We review your DMARC policy to ensure it isn't over-aggressive and isn't catching legitimate mail in its reject or quarantine net.
Blocklist check
We run your domain and sending IPs against major blocklists (Spamhaus, Barracuda, Microsoft SNDS) to identify reputation issues.
Remediation and testing
We make the corrections, wait for DNS propagation, and send live test messages to confirm delivery end-to-end.
DNS email problems are fully solvable — and once fixed, they stay fixed. Maryland businesses trust NVT to get their email working correctly the first time.
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