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Suddenly, most sites have invalid signature. That includes sites that I visit on a regular basis. Firefox is unusable-I can't visit most sites

  • 3 replies
  • 1 has this problem
  • 6 views
  • Last reply by cor-el

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secure connection failed- all of a sudden, this is most sites, including sites I visit daily

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You can check the date and time and time zone in the clock on your computer: (double) click the clock icon on the Windows Taskbar.

You can check if there is more detail available about the issuer of the certificate.

  • click the "Advanced" button show more detail
  • click the blue error text (SEC_ERROR_UNKNOWN_ISSUER) to show the certificate chain
  • click "Copy text to clipboard" and paste the base64 certificate chain text in a reply

If clicking the blue error text doesn't provide the certificate chain then try these steps to inspect the certificate.

  • open the Servers tab in the Certificate Manager
    • Options/Preferences -> Privacy & Security
      Certificates: View Certificates -> Servers: "Add Exception"
  • paste the URL of the website (https://xxx.xxx) in it's Location field

Let Firefox retrieve the certificate -> "Get Certificate"

  • click the "View" button and inspect the certificate

You can see detail like the issuer of the certificate and intermediate certificates in the Details tab.