Hostname Mismatch
The certificate is valid but does not list the name in the address bar, such as a certificate for example.com served on www.example.com. Check the site below to confirm what is wrong.
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SSL Certificate Checker
The error, and the fix
Error CodesNET::ERR_CERT_COMMON_NAME_INVALID
Usual CauseThe certificate is valid but does not list the name in the address bar, such as a certificate for example.com served on www.example.com
Check From a Terminalopenssl s_client -connect example.com:443 -servername example.com
The certificate is valid but does not list the name in the address bar, such as a certificate for example.com served on www.example.com.
How to fix it: Issue a certificate that covers every name the site answers on (certbot -d example.com -d www.example.com), or redirect the other names.
Questions
What does "hostname mismatch" mean?
The certificate is valid but does not list the name in the address bar, such as a certificate for example.com served on www.example.com.
How do I fix it?
Issue a certificate that covers every name the site answers on (certbot -d example.com -d www.example.com), or redirect the other names.
Is it safe to click through the warning?
Not on a site where you enter passwords or payment details: the connection may not be private. Fix the certificate instead.
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