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SecurityCritical

Invalid TLS certificate

The certificate does not validate (expired, wrong host or broken chain) — browsers show a full-page warning.

2.7%of Global websites

By market

  1. Global2.7%
  2. United Kingdom1.3%
  3. Netherlands1.9%
  4. Italy2.8%
  5. Spain3.6%
  6. Japan4.6%
  7. Latin America3.6%

How to fix

  1. 1Check the certificate with our SSL checker.
  2. 2Renew it or install the missing intermediate certificates.
  3. 3Make sure the certificate covers both the apex and www.

Related mistakes

Our crawler: 68,769 sites · Global · updated Oct 23, 2026 · Methodology

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