Self-Signed Certificate
The server presents a certificate it signed itself, which browsers cannot trust. Common on fresh installs, panels and appliances. Check the site below to confirm what is wrong.
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Examples:
SSL Certificate Checker
The error, and the fix
Error CodesNET::ERR_CERT_AUTHORITY_INVALID · DEPTH_ZERO_SELF_SIGNED_CERT
Usual CauseThe server presents a certificate it signed itself, which browsers cannot trust
Check From a Terminalopenssl s_client -connect example.com:443 -servername example.com
The server presents a certificate it signed itself, which browsers cannot trust. Common on fresh installs, panels and appliances.
How to fix it: Replace it with a free certificate from Let's Encrypt (certbot --nginx or --apache), or put the service behind a reverse proxy that has one.
Questions
What does "self-signed certificate" mean?
The server presents a certificate it signed itself, which browsers cannot trust. Common on fresh installs, panels and appliances.
How do I fix it?
Replace it with a free certificate from Let's Encrypt (certbot --nginx or --apache), or put the service behind a reverse proxy that has one.
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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