ERR_CERT_DATE_INVALID 🟨 JavaScript

NET::ERR_CERT_DATE_INVALID (certificate expired)

The site’s certificate has expired (or isn’t valid yet) — or the device clock is wrong.

Seen on: JavaScript

Meaning

Let’s Encrypt certificates last 90 days; failed auto-renewal is the usual cause. A wrong system date on the visitor’s device shows the same error.

Common causes

  • Certificate expired (renewal failed)
  • Device clock/date wrong
  • Old intermediate in the chain expired

⚡ Quick fix

  1. Renew the certificate and reload the web server
  2. Fix certbot renewal (check the timer and logs)
  3. Correct the device date/time

Detailed fix by platform

Linux

  1. sudo certbot renew && sudo systemctl reload nginx

How to diagnose

  1. Expiry — Check the certificate’s notAfter date
  2. Clock — Is the device time correct?

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