Exact error diagnosisReviewed 2026-08-07By HostWithShery technical editorial

NET::ERR_CERT_COMMON_NAME_INVALID

The certificate does not cover the hostname the browser requested.

Start with evidence from your own domain before changing DNS, SSL or mail settings.
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What this error means

The certificate does not cover the hostname the browser requested. The browser or proxy message describes the symptom, not necessarily the root cause. HostWithShery therefore checks the TLS, certificate and HTTPS evidence that can be observed publicly before recommending a configuration change.

Most likely causes

These are the first explanations to test because each can produce this exact symptom. Treat them as hypotheses until the matching public evidence is present.

  • Certificate issued only for root or wwwTest the hostname actually requested, its certificate dates and SAN coverage, and the TLS handshake. Root and www can serve different certificates.
  • Wrong certificate served by virtual hostTest the hostname actually requested, its certificate dates and SAN coverage, and the TLS handshake. Root and www can serve different certificates.
  • Stale certificate after migrationTest the hostname actually requested, its certificate dates and SAN coverage, and the TLS handshake. Root and www can serve different certificates.

What to check on your domain

Use the embedded scan to compare the failing layer with adjacent layers that can produce the same visible error. This prevents a DNS change from being used to “fix” a TLS problem, or an SSL-mode change from masking an origin failure.

  • Certificate issued only for root or wwwTest the hostname actually requested, its certificate dates and SAN coverage, and the TLS handshake. Root and www can serve different certificates.
  • Wrong certificate served by virtual hostTest the hostname actually requested, its certificate dates and SAN coverage, and the TLS handshake. Root and www can serve different certificates.
  • Stale certificate after migrationTest the hostname actually requested, its certificate dates and SAN coverage, and the TLS handshake. Root and www can serve different certificates.
  • Issue a certificate covering the hostnameTest the hostname actually requested, its certificate dates and SAN coverage, and the TLS handshake. Root and www can serve different certificates.
  • Fix virtual-host/SNI mappingVerify fix virtual-host/SNI mapping from the public Internet and compare it with the value the responsible provider says should be live.

Fixes in the recommended order

Change the smallest confirmed layer first. Preserve working DNS and mail records, document the current value, apply one repair, and then retest before moving to the next possibility.

  • 1. Issue a certificate covering the hostname. Confirm the public result after this step before making another unrelated change.
  • 2. Fix virtual-host/SNI mapping. Confirm the public result after this step before making another unrelated change.
  • 3. Test root and www separately. Confirm the public result after this step before making another unrelated change.

How to confirm the repair

HTTPS should complete for the exact hostname, the certificate should be valid for that hostname, and root/www should follow the intended canonical redirect without a TLS error.

If the error remains

Capture the checked hostname, exact timestamp, final DNS addresses, redirect/TLS result and the failing public status before escalating. That evidence gives a hosting or provider support team something testable instead of only the browser message. If results differ by resolver or network, include those differences rather than assuming the failure is universal.

What not to change

Do not replace nameservers, delete unrelated mail records, disable security controls, remove IPv6 blindly or purge the entire configuration merely because this message appears. Diagnose the failing layer first; broad changes can turn one isolated fault into several independent faults.

Technical references

These primary standards and provider documents are used to verify the behavior described on this page. Provider dashboards can change, so use the current official value for tenant-specific DNS records rather than copying an example from another account.