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Firefox 8 not displaying addons, error code:sec_error_unknown_issuer

  • 3 replies
  • 8 have this problem
  • 1 view
  • Last reply by cor-el

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I receive the following error message when opening the addons tool bar...

support.mozilla.com uses an invalid security certificate.

The certificate is not trusted because the issuer certificate is unknown.

(Error code: sec_error_unknown_issuer)

I receive the following error message when opening the addons tool bar... support.mozilla.com uses an invalid security certificate. The certificate is not trusted because the issuer certificate is unknown. (Error code: sec_error_unknown_issuer)

All Replies (3)

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Check the date and time in the clock on your computer: (double) click the clock icon on the Windows Taskbar.

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Thanks for the reply, but I checked and my date and time system settings are correct. Is there another reason why this would be happening. I have uninstalled/reinstalled firefox a number of times with no success.

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Did you check the details of that certificate like the issuer and when it is valid by retrieving the certificate?

  • Click the link at the bottom of the error page: "I Understand the Risks"

Let Firefox retrieve the certificate: "Add Exception" -> "Get Certificate".

  • Click the "View..." button and inspect the certificate and check who is the issuer.

You can see more Details like intermediate certificates that are used in the Details pane.