LightAtom

ERR_SSL_UNRECOGNIZED_NAME_ALERT: How to Fix It

During the TLS handshake the server said it doesn't host the name you asked for (SNI), usually a server configuration problem or a wrong address.

ERR_SSL_UNRECOGNIZED_NAME_ALERT

Your browser told the server which site it wanted (the host name), and the server answered that it doesn't serve that name.

Quick checks

  • Try the address with or without www.
  • Check DNS points to the right server (hosts file, VPN).

Fixes on Mac

  1. Check where the name resolves

    1. Run dig +short example.com and compare with what the site's owner expects.
    2. Check /etc/hosts for stale entries.

  2. Turn off proxies and VPNs

    1. They can route you to a different server that doesn't know the name.

Fixes on Windows

  1. Check hosts file and proxy

    1. Look for stale entries in the Windows hosts file; disable unused proxies.

Other devices

  1. Other devices

    1. Try mobile data to rule out your network's DNS.

Still not working?

Site owners: the server has no virtual host or certificate for the requested name. Add the name to server_name (nginx) or ServerName/ServerAlias (Apache) with a matching certificate, or fix the DNS record that points the name to this server.

See what’s happening

LightAtom's connections view shows the IP address your browser actually connected to for that name.

Frequently asked questions

What is SNI?

Server Name Indication: the host name a client sends at the start of the TLS handshake, so one server can host many HTTPS sites. This error is the server rejecting that name.

Can I fix it as a visitor?

Only if your DNS sends you to the wrong server. Otherwise the site's owner must configure the name on their server.

Why does www work but the bare domain doesn't?

The server is configured for one name only. The owner should add the other name or redirect it.

Related errors and tools

Related

LightAtom team

The people who build LightAtom, a network monitor for macOS.