LightAtom

"Your Connection Is Not Private": What It Means and What to Do

Chrome couldn't verify the website's identity because its HTTPS certificate failed a check. Sometimes the site is broken; sometimes your clock, network or software is the cause.

Your connection is not private

The website's security certificate failed a check, so the browser can't confirm you're talking to the real site. Anything you send could be read or changed.

Quick checks

  • Read the code under the message: NET::ERR_CERT_DATE_INVALID, ERR_CERT_AUTHORITY_INVALID or ERR_CERT_COMMON_NAME_INVALID each point to a different cause.
  • Check your Mac's date and time.
  • On public Wi-Fi, open an http:// site first to get the login page.
  • Never enter passwords or card details while this warning shows.

Fixes on Mac

  1. Fix the date and time

    1. System Settings › General › Date & Time: turn on Set time and date automatically.

  2. Log in to public Wi-Fi

    1. Hotels, airports and cafés intercept pages until you accept their terms. Open http://captive.apple.com to bring up the login page, then retry.

  3. Turn off HTTPS-inspecting software

    1. Antivirus web shields, parental-control apps and debugging proxies (Charles, Proxyman) replace certificates. Pause them and retry.
    2. If you installed a proxy's root certificate, remove it in Keychain Access when you no longer need it.

  4. Update macOS and the browser

    1. Old systems lack newer root certificates. Install updates in System Settings › General › Software Update.

Fixes on Windows

  1. Fix the clock and check security software

    1. Settings › Time & language › Date & time: set time automatically and sync now.
    2. Turn off HTTPS scanning in your antivirus to test.

Other devices

  1. Phones

    1. Turn on automatic date and time.
    2. On public Wi-Fi, complete the login page first.

Still not working?

When to stop: if the warning appears on your bank, email or any site where you log in, and the steps above don't fix it, don't continue. On a public network, someone may be intercepting traffic.

If you run the site: check the certificate hasn't expired, covers the exact host name (including www), and that the server sends the intermediate certificates. openssl s_client -connect example.com:443 -servername example.com shows the chain.

See what’s happening

LightAtom's connections view shows whether your browser connects to a proxy address instead of the site's servers, and which process runs that proxy.

Frequently asked questions

Is it safe to click “Proceed” on “Your connection is not private”?

Only on sites you control or that you know use a self-signed certificate, like your router's admin page. Never for banking, shopping, email or any login on a network you don't trust.

Why does this happen on every website?

Something on your side: a wrong clock, a captive-portal Wi-Fi, or software that inspects HTTPS. Fix the clock first, then check public Wi-Fi and security apps.

Why does it only happen on one network?

That network intercepts HTTPS: a hotel or café login page, a school or office filter, or, rarely, an attacker. Use mobile data or a VPN for sensitive sites.

What is the Safari version of this error?

Safari says “This Connection Is Not Private”. Firefox says “Warning: Potential Security Risk Ahead”. The causes are the same.

Can an expired certificate on the site cause this?

Yes, then everyone sees it and only the site owner can fix it by renewing the certificate.

Related errors and tools

Related

LightAtom team

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