Guides & reference
Get to the cause of a certificate warning
A certificate can be in date and still fail verification. CheckSSL examines the TLS connection on port 443, including trust, hostname and validity. These guides help you distinguish an approaching expiry from a name mismatch or a chain problem, so you can investigate the right part of your hosting setup.
How to check SSL certificate expiry and renewal
Read certificate dates, verify a renewal on the public endpoint and investigate why a server still presents an old certificate.
Read guide Hostname errorsHow to troubleshoot an SSL certificate name mismatch
Understand hostname coverage, wildcard limits and why an HTTPS redirect cannot fix a certificate for the wrong name.
Read guide Certificate trustSSL certificate chain errors: what to investigate
Understand leaf, intermediate and root certificates, and investigate a failed trust check without guessing the cause.
Read guideTLS certificate reference: trust, names, expiry and protocol checks
Interpret certificate and TLS findings, including unknown verification, received chains, revocation and protocol probes.
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