Chrome, Edge

NET::ERR_CERT_AUTHORITY_INVALID

The certificate was not issued by an authority the browser trusts — commonly a self-signed certificate, or a missing intermediate.

What causes it

A self-signed certificate on a public site.
A missing intermediate certificate, which works in some browsers and fails in others.
Corporate TLS inspection installing its own root.
An origin certificate from a CDN being served directly.

If you are the visitor

If it is your own internal server, this may be expected — but never click through on a site handling passwords or payments.
Check whether other devices see the same error; if only yours does, suspect local antivirus or a corporate proxy.

If it is your website

Install a certificate from a public authority such as Let's Encrypt.
Serve the full chain file, not just the certificate.

Find out whether the site is down for everyone

A live check from our server shares nothing with your network — it settles the question in seconds.

Run a live check

Other connection errors

ERR_CONNECTION_REFUSED DNS_PROBE_FINISHED_NXDOMAIN ERR_NAME_NOT_RESOLVED ERR_CONNECTION_TIMED_OUT ERR_SSL_PROTOCOL_ERROR NET::ERR_CERT_DATE_INVALID NET::ERR_CERT_COMMON_NAME_INVALID ERR_TOO_MANY_REDIRECTS ERR_EMPTY_RESPONSE ERR_CONNECTION_RESET 503 Service Unavailable 502 Bad Gateway This site can't be reached