NET::ERR_CERT_AUTHORITY_INVALID: Complete Fix Guide
· CSR.plus Team
- •This error means no trusted CA in the client’s store issued the certificate presented by the server.
- •The most common real cause is a missing intermediate certificate, not a malicious site.
- •Fix the server chain, or if you are a visitor, check the date and trust store before assuming the worst.
What the browser is telling you
When Chrome shows NET::ERR_CERT_AUTHORITY_INVALID it could not chain the server’s certificate back to a root in its trust store. The page may still be reachable through "Advanced > Proceed", which is only safe when you are sure the error is a configuration issue, not an attack.
For site owners: fix the server
Fetch the full chain and deploy leaf + intermediates in order (see the incomplete chain guide). Replace any certificate whose root has expired (older SHA-1 era roots still chain-fail on some clients). If you use an internal CA, install its root into the client trust stores and keep the root’s CRL reachable. Never serve a self-signed leaf on a public site.
For visitors: quick checks
Check your system clock (a wrong date breaks every certificate check), try another network, and try a different browser. If the error disappears elsewhere, the issue is local. If it persists everywhere, the site itself is misconfigured — report it to the owner.
FAQ
Is it safe to click "Proceed anyway"?
Only if you are certain the site is legitimate and the certificate problem is a server configuration issue (e.g., you manage the site). On any public site you did not initiate, treat it as a warning and leave.
Does antivirus software cause this error?
Yes. TLS-inspecting antivirus or corporate proxies present their own CA. If the error appears on many sites at once, your AV/proxy certificate or clock is the likely cause.
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