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"SEC_ERROR_UNKNOWN_ISSUER".

  • 2 replies
  • 2 have this problem
  • 17 views
  • Last reply by cor-el

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I have installed a SSL certificate on our server which hosts https://slotshotel.dk. In Firefox I got the error "SEC_ERROR_UNKNOWN_ISSUER" on multiple PC's and different versions.

In all other browsers the certificate works well.

Google Chrome 58.0.3029.110 (64-bit) Microsoft Edge 38.14393.1066.0 Internet Explorer, 11.1198.14393.0

What to do?
I have installed a SSL certificate on our server which hosts https://slotshotel.dk. In Firefox I got the error "SEC_ERROR_UNKNOWN_ISSUER" on multiple PC's and different versions. In all other browsers the certificate works well. Google Chrome 58.0.3029.110 (64-bit) Microsoft Edge 38.14393.1066.0 Internet Explorer, 11.1198.14393.0 What to do?

All Replies (2)

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uses an invalid security certificate SSL_ERROR_BAD_CERT_DOMAIN
configured their website improperly

How to troubleshoot the error code "SEC_ERROR_UNKNOWN_ISSUER" on secure websites https://support.mozilla.org/en-US/kb/troubleshoot-SEC_ERROR_UNKNOWN_ISSUER

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Who is the issuer of the certificate?

You can click the "Advanced" button to expand this section to see extra details. If the certificate is not trusted because no issuer chain was provided (SEC_ERROR_UNKNOWN_ISSUER) then click the blue error message to expand this section and to show the certificate chain. You can paste the full base64 encoded certificate chain in a reply. Then we can check the issuer.