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

  • 1 reply
  • 7 have this problem
  • 25 views
  • Last reply by cor-el

pbyrum
pbyrum
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Hello,

When viewing my site https://www.site.com I see this error:

https://www.site.com uses an invalid security certificate. The certificate is not trusted because the issuer certificate is unknown. (Error code: sec_error_unknown_issuer)

I am using FireFox 38.0.5 on a Windows 8.1 PC. The same site on the same PC is displayed fine with no certificate errors when using MS 11 and Google Chrome.

I have deleted the cert8.db file, but that did not work. I followed these steps:

www.site.com uses an invalid security certificate. The certificate is not trusted because the issuer certificate is unknown. (Error code: sec_error_unknown_issuer)

Do you have another suggestions?

Thanks,

Paul

Hello, When viewing my site https://www.site.com I see this error: https://www.site.com uses an invalid security certificate. The certificate is not trusted because the issuer certificate is unknown. (Error code: sec_error_unknown_issuer) I am using FireFox 38.0.5 on a Windows 8.1 PC. The same site on the same PC is displayed fine with no certificate errors when using MS 11 and Google Chrome. I have deleted the cert8.db file, but that did not work. I followed these steps: www.site.com uses an invalid security certificate. The certificate is not trusted because the issuer certificate is unknown. (Error code: sec_error_unknown_issuer) Do you have another suggestions? Thanks, Paul

All Replies (1)

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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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 retrieve the certificate and check details like who issued certificates and expiration dates of certificates.

  • 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 the intermediate certificates that are used in the Details tab.

Who is the issuer of the certificate?